Neurochemistry: Molecular, Cellular and Medical Neurobiology

Sarvarthapedia

Sarvarthapedia (Core Areas)

Below is a comprehensive, structured outline of Neurochemistry: Molecular, Cellular and Medical Neurobiology (up to 2026), under Chemistry, spanning 12 volumes. Each volume covers fundamental neurochemistry, molecular signaling, cellular neurobiology, neuropharmacology, neuroimmunology, metabolic pathways, neurodegenerative and psychiatric neurochemistry, developmental neurobiology, injury and repair, emerging technologies, and clinical translation.

Volume 1: Foundations of Neurochemistry – History, Molecules, and Methods

Part I: Defining Neurochemistry

• Historical origins (Thudichum, 1884 – “chemical constitution of the brain”)
• Relationship to neuroscience, molecular biology, and pharmacology
• The neuron doctrine and chemical transmission (Loewi, Dale, Eccles)
• Major milestones: identification of neurotransmitters, second messengers, receptors

Part II: The Chemical Composition of the Nervous System

• Water, ions, and electrolytes
• Amino acids, biogenic amines, neuropeptides
• Lipids (phospholipids, sphingolipids, cholesterol, gangliosides)
• Carbohydrates and glycoconjugates
• Nucleic acids (DNA, RNA, non-coding RNAs)
• Energy metabolites (ATP, phosphocreatine, lactate)

Part III: Basic Biochemical Principles

• Protein structure and function (primary to quaternary, post-translational modifications)
• Enzymology in neurochemistry (kinetics, regulation, cofactors)
• Membrane biochemistry (lipid bilayers, membrane proteins, ion channels)
• Thermodynamics and transport across the blood-brain barrier (BBB)

Part IV: Core Neurochemical Methods

• Tissue homogenization, subcellular fractionation (synaptosomes, myelin, mitochondria)
• Chromatography (HPLC, GC-MS, LC-MS/MS) for neurotransmitters and metabolites
• Immunohistochemistry and immunofluorescence
• In situ hybridization (ISH, RNAscope)
• Western blotting and ELISA
• Microdialysis and voltammetry (fast-scan cyclic voltammetry, FSCV)
• Mass spectrometry imaging (MALDI-MSI, DESI)
• Single-cell neurochemical profiling (patch-seq, scRNA-seq, scATAC-seq)

Part V: Model Systems in Neurochemistry

• Primary neuronal and glial cultures
• Brain slices (acute, organotypic)
• Invertebrate models (Aplysia, Drosophila, C. elegans)
• Rodent models (mouse, rat, transgenic/knockout lines)
• Human iPSC-derived neurons and brain organoids
• Emerging: 3D bioprinted neural tissues

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Volume 2: Neurotransmitters and Neuromodulators – Synthesis, Storage, Release

Part I: Small Molecule Neurotransmitters

• Glutamate – synthesis (glutaminase), vesicular transport (VGLUTs), recycling (EAATs)
• GABA – synthesis (GAD65/67), vesicular transport (VGAT), catabolism (GABA-T)
• Glycine – synthesis, transport (GlyT1/2), strychnine-sensitive receptors
• Acetylcholine – synthesis (ChAT), vesicular transport (VAChT), degradation (AChE)
• Dopamine – synthesis (tyrosine hydroxylase, DOPA decarboxylase), vesicular transport (VMAT2), catabolism (MAO, COMT)
• Norepinephrine – synthesis (dopamine β-hydroxylase), vesicular transport
• Epinephrine – synthesis (PNMT), adrenal vs. brain
• Serotonin (5-HT) – synthesis (tryptophan hydroxylase 1/2, aromatic L-amino acid decarboxylase), vesicular transport (VMAT2)
• Histamine – synthesis (histidine decarboxylase), HDC knockout phenotypes

Part II: Neuropeptides

• Biosynthesis (prepropeptide → propeptide → active peptide)
• Peptide processing enzymes (prohormone convertases PC1/3, PC2, carboxypeptidase E)
• Major families:
• Opioid peptides (β-endorphin, enkephalins, dynorphins)
• Tachykinins (substance P, neurokinin A/B)
• Neurohypophyseal hormones (vasopressin, oxytocin)
• Hypothalamic releasing hormones (CRH, TRH, GnRH, GHRH, somatostatin)
• Neuropeptide Y (NPY)
• Galanin, orexin/hypocretin, melanin-concentrating hormone (MCH)
• Corticotropin-releasing factor (CRF)
• Brain-derived neurotrophic factor (BDNF) and other neurotrophins
• Co-transmission (neuropeptide + small molecule)

Part III: Gaseous and Unconventional Transmitters

• Nitric oxide (NO) – synthesis (nNOS, eNOS, iNOS), targets (guanylyl cyclase), role in synaptic plasticity
• Carbon monoxide (CO) – heme oxygenase (HO-1, HO-2)
• Hydrogen sulfide (H₂S) – CBS, CSE, MPST
• Endocannabinoids – anandamide (AEA), 2-arachidonoylglycerol (2-AG), synthesis (NAPE-PLD, DAGL), degradation (FAAH, MAGL)

Part IV: Vesicular Release Machinery

• Synaptic vesicle cycle (SV2, synaptotagmin, synapsin, synaptobrevin/VAMP)
• SNARE complex (syntaxin, SNAP-25, VAMP)
• Calcium-triggered fusion (synaptotagmin as Ca²⁺ sensor)
• Kiss-and-run vs. full fusion
• Quantal release and quantal analysis (del Castillo & Katz)

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Volume 3: Receptors, Ion Channels, and Signal Transduction

Part I: Ligand-Gated Ion Channels (Ionotropic Receptors)

• Glutamate receptors – AMPA (GluA1-4), kainate (GluK1-5), NMDA (GluN1, GluN2A-D, GluN3A-B)
• NMDA receptor co-agonists (glutamate + glycine/D-serine), Mg²⁺ block, Ca²⁺ permeability
• GABA-A receptors – subunit composition (α1-6, β1-3, γ1-3, δ, ε, θ, π, ρ1-3), benzodiazepine and barbiturate binding sites
• Glycine receptors (α1-4, β) – strychnine antagonism
• Nicotinic acetylcholine receptors (α2-10, β2-4) – homomeric vs. heteromeric
• Serotonin 5-HT3 receptor – cation channel
• P2X receptors (ATP-gated, P2X1-7)
• Zinc-activated channels (ZAC)

Part II: G Protein-Coupled Receptors (GPCRs)

• GPCR superfamily structure (7-transmembrane domains)
• G protein subunits (Gαs, Gαi/o, Gαq/11, Gα12/13) – effectors (adenylyl cyclase, PLC, ion channels)
• Specific GPCRs by neurotransmitter:
• Dopamine (D1-like: D1, D5; D2-like: D2, D3, D4)
• Norepinephrine (α1A/B/D, α2A/B/C, β1-3)
• Serotonin (5-HT1A/B/D/E/F, 5-HT2A/B/C, 5-HT4, 5-HT5A/B, 5-HT6, 5-HT7)
• Acetylcholine (muscarinic M1-M5)
• GABA-B (GABA-B1, GABA-B2)
• Glutamate (mGluR1-8, groups I/II/III)
• Opioid (μ, δ, κ, nociceptin/orphanin FQ)
• Cannabinoid (CB1, CB2)
• Adenosine (A1, A2A, A2B, A3)
• Histamine (H1-H4)
• Neuropeptide receptors (NPY Y1-5, CRF1/2, orexin OX1/2, etc.)

Part III: Receptor Regulation and Trafficking

• Desensitization (homologous vs. heterologous)
• β-arrestin pathways (G protein-independent signaling)
• Endocytosis (clathrin, caveolin) and recycling
• Ubiquitination and lysosomal degradation

Part IV: Second Messenger Systems

• cAMP/PKA pathway – adenylyl cyclase isoforms, phosphodiesterases (PDEs), CREB
• Phosphoinositide (PI) pathway – PLCβ, IP3, DAG, PKC, Ca²⁺ release
• Calcium signaling – intracellular stores (ER), calmodulin (CaM), CaMKII, calcineurin
• MAPK/ERK pathway (Ras/Raf/MEK/ERK) – role in plasticity and growth
• PI3K/Akt/mTOR pathway – cell survival, translation
• Nitric oxide/cGMP/PKG pathway

Part V: Ion Channels (Voltage-Gated and Others)

• Voltage-gated sodium channels (Nav1.1-1.9) – structure, inactivation, toxin binding (tetrodotoxin, saxitoxin)
• Voltage-gated calcium channels (Cav1.x L-type, Cav2.x P/Q/N/R-type, Cav3.x T-type)
• Voltage-gated potassium channels (Kv1-12) – delayed rectifier, A-type, M-current
• Inward rectifier potassium channels (Kir) – GIRK channels
• Two-pore domain potassium channels (K2P) – leak channels
• Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels – Iₕ current
• Transient receptor potential (TRP) channels (TRPV1-4, TRPM1-8, TRPC1-7, TRPA1, TRPML, TRPP) – thermosensation, mechanosensation, chemosensation

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Volume 4: Cellular Neurobiology – Neurons, Glia, and Synaptic Plasticity

Part I: Neuronal Structure and Compartments

• Axonal transport (kinesin anterograde, dynein retrograde) – fast and slow components
• Dendritic spines – morphology, plasticity, spine apparatus
• Axon initial segment (AIS) – ion channel clustering, action potential initiation
• Presynaptic terminal – active zone, reserve pool, recycling pool

Part II: Glial Neurochemistry

• Astrocytes – glutamate uptake (EAAT1/2), glutamine synthetase, glycogen storage, lactate shuttle (ANLS), K⁺ buffering, gliotransmission (ATP, D-serine, glutamate)
• Oligodendrocytes – myelin synthesis (MBP, PLP, MAG, MOG), cholesterol and lipid metabolism, activity-dependent myelination
• Microglia – immune surveillance, cytokine release (IL-1β, TNF-α, IL-6), phagocytosis, TREM2, CX3CR1, P2Y12 receptors
• NG2 glia (polydendrocytes) – proliferation, differentiation into oligodendrocytes
• Ependymal cells – CSF secretion (choroid plexus)

Part III: Synaptic Transmission and Plasticity

• Quantal release and the Katz model
• Short-term plasticity (facilitation, augmentation, potentiation, depression)
• Long-term potentiation (LTP) – NMDA-dependent (CA1), mossy fiber (cAMP-dependent), timing-dependent (STDP)
• Long-term depression (LTD) – metabotropic glutamate receptor-dependent (cerebellum, hippocampus)
• Homeostatic plasticity (synaptic scaling) – TNF-α, Arc, retinoic acid
• Spike-timing-dependent plasticity (STDP) – Hebbian and anti-Hebbian windows

Part IV: Metabolism and Energetics

• Brain energy consumption (20% of body’s O₂ at 2% mass)
• Glucose metabolism – glycolysis, TCA cycle, oxidative phosphorylation
• Ketone bodies as alternative fuel (ketogenic diet mechanisms)
• Lactate shuttle (astrocyte–neuron) – controversy and evidence
• Creatine kinase system
• Hypoxia and energy failure (ischemic cascade)

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Volume 5: Neurochemistry of Development and Aging

Part I: Neural Development – Molecular Mechanisms

• Neural induction (BMP inhibition, noggin, chordin, follistatin)
• Neurogenesis (Ngn1/2, Ascl1, NeuroD) – embryonic and adult (subventricular zone, dentate gyrus)
• Neuronal migration (reelin, Dab1, Cdk5, Lis1, doublecortin)
• Axon guidance – netrin/DCC, slit/robo, semaphorin/neuropilin/plexin, ephrin/Eph
• Synaptogenesis – neurexin/neuroligin, LRRTMs, cerebellin/GluD2
• Programmed cell death – caspases, Bcl-2 family, neurotrophin dependence (NGF, BDNF, NT-3, NT-4)
• Myelination (developmental timeline, growth factors: PDGF, FGF, IGF-1)

Part II: Neurotrophins and Growth Factors

• NGF – TrkA, p75NTR, retrograde signaling
• BDNF – TrkB, proBDNF, role in LTP and depression
• NT-3 – TrkC
• NT-4 – TrkB
• GDNF family (GDNF, neurturin, artemin, persephin) – Ret/GFRα receptors
• CNTF, LIF, cardiotrophin-1 – gp130 signaling

Part III: Adult Neurogenesis

• Neurogenic niches (SVGZ, SGZ)
• Molecular regulation (Wnt, Notch, Shh, BMP)
• Environmental influences (exercise, enrichment, stress, antidepressants)
• Functional roles in olfaction, memory, and mood

Part IV: Aging Neurochemistry

• Oxidative stress – reactive oxygen species (ROS), superoxide dismutase (SOD), catalase, glutathione peroxidase, mitochondrial dysfunction
• Protein aggregation – tau, α-synuclein, Aβ, TDP-43, huntingtin
• Decline in neurotransmitter systems (dopamine in substantia nigra, acetylcholine in basal forebrain)
• Calcium dysregulation hypothesis of aging
• Senescence (p16INK4a, p21, SASP) in glia
• Sirtuins (SIRT1-7) and NAD⁺ metabolism in brain aging
• Autophagy decline and mitophagy

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Volume 6: Neurochemistry of Neurodegenerative Diseases

Part I: Alzheimer’s Disease (AD)

• Amyloid precursor protein (APP) processing – α-, β-, γ-secretases
• Aβ peptides (Aβ40, Aβ42) – oligomers, fibrils, plaques
• Tau protein – phosphorylation (GSK3β, CDK5, MARK), aggregation, neurofibrillary tangles
• APOE4 isoform – lipid transport, microglial function
• Neuroinflammation in AD – TREM2, complement, NLRP3 inflammasome
• Biomarkers – CSF Aβ42/p-tau/t-tau, plasma p-tau217, amyloid/tau PET
• Metabolic dysfunction – glucose hypometabolism (FDG-PET), mitochondrial defects

Part II: Parkinson’s Disease (PD)

• Dopamine neuron loss in substantia nigra pars compacta
• α-Synuclein (SNCA) – Lewy bodies, oligomers, prion-like spreading
• Parkin (PARK2), PINK1, DJ-1, LRRK2, GBA mutations – mitochondrial and lysosomal pathways
• Oxidative stress and iron accumulation (ferroptosis)
• Neuromelanin
• Biomarkers – α-synuclein seeding amplification assay (SAA) from CSF
• Gut-brain axis and vagal spread hypothesis

Part III: Huntington’s Disease (HD)

• CAG repeat expansion in huntingtin (HTT) – polyglutamine tract
• Mutant huntingtin aggregation (nuclear and cytoplasmic)
• Transcriptional dysregulation (Sp1, CREB, PGC-1α)
• Striatal medium spiny neuron vulnerability
• Metabolic deficits and mitochondrial dysfunction

Part IV: Amyotrophic Lateral Sclerosis (ALS)

• SOD1 mutations – oxidative damage, protein aggregation
• TDP-43 pathology (cytoplasmic inclusions, loss of nuclear function)
• C9orf72 hexanucleotide repeat expansion – dipeptide repeat proteins (DPRs), gain-of-function
• FUS, TBK1, OPTN, VCP, UBQLN2 mutations
• Glial contributions (astrocyte and microglial toxicity to motor neurons)

Part V: Prion Diseases

• Prion protein (PrPᶜ) to scrapie isoform (PrPˢᶜ) conversion
• Strain phenomena and species barriers
• Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker (GSS), fatal familial insomnia (FFI)

Part VI: Other Neurodegenerative Disorders

• Frontotemporal dementia (FTD) – tau (MAPT), progranulin (GRN), C9orf72
• Lewy body dementia (DLB)
• Multiple system atrophy (MSA) – glial cytoplasmic inclusions (α-synuclein)
• Progressive supranuclear palsy (PSP) – tau (4R)
• Corticobasal degeneration (CBD)

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Volume 7: Neurochemistry of Psychiatric Disorders

Part I: Schizophrenia

• Dopamine hypothesis (hyperdopaminergia in striatum, hypodopaminergia in prefrontal cortex)
• Glutamate hypothesis (NMDA receptor hypofunction – ketamine/PCP model)
• GABAergic interneuron deficits (parvalbumin-positive, somatostatin-positive)
• Myelin and oligodendrocyte abnormalities
• kynurenine pathway metabolites (quinolinic acid, kynurenic acid)
• Antipsychotic mechanisms – D2 antagonism, 5-HT2A antagonism, partial agonism

Part II: Major Depressive Disorder (MDD)

• Monoamine hypotheses (serotonin, norepinephrine, dopamine) – limitations
• Neurotrophic hypothesis (BDNF, TrkB, VEGF)
• Glutamate hypothesis (ketamine’s rapid antidepressant effect via NMDA antagonism)
• GABAergic deficits
• HPA axis hyperactivity (CRH, cortisol, GR resistance)
• Inflammatory hypothesis (IL-6, TNF-α, CRP, IDO activation, tryptophan depletion)
• Metabolic and mitochondrial dysfunction

Part III: Bipolar Disorder

• Mania and depression neurochemistry – dopamine, norepinephrine, GABA, glutamate
• Lithium’s mechanisms – inositol depletion (IMPA), GSK3β inhibition, neuroprotection
• Valproate and lamotrigine – effects on sodium channels, GABA

Part IV: Anxiety and PTSD

• GABA/glutamate balance in amygdala and prefrontal cortex
• Serotonin (5-HT1A, 5-HT2A, 5-HT3)
• Neuropeptide Y (NPY) – anxiolytic
• CRH – anxiogenic
• Endocannabinoid system (anandamide, 2-AG) – stress buffering

Part V: Substance Use Disorders

• Mesolimbic dopamine pathway (VTA → NAc) – reward
• Drugs of abuse mechanisms:
• Cocaine (DAT blockade)
• Amphetamines (reverse DAT transport)
• Opioids (μ receptor activation, disinhibition of VTA dopamine neurons)
• Nicotine (α4β2 nAChR activation)
• Alcohol (GABA-A positive allosteric modulation, NMDA antagonism)
• Cannabis (CB1 receptor activation)
• Neuroadaptations – ΔFosB, CREB, dynorphin, glutamate plasticity
• Withdrawal and negative affect (CRH, noradrenaline)

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Volume 8: Neurochemistry of Pain, Sleep, and Circadian Rhythms

Part I: Pain Neurochemistry

• Nociceptor transduction – TRPV1 (capsaicin, heat), TRPA1 (mustard oil, cold), ASICs, P2X3
• Peripheral sensitization – bradykinin, prostaglandins (COX), NGF, CGRP, substance P
• Spinal cord transmission – glutamate (NMDA, AMPA), substance P (NK1), BDNF
• Central sensitization – wind-up, PKCγ, ERK
• Descending modulation – periaqueductal gray (PAG), rostral ventromedial medulla (RVM)
• Opioidergic (β-endorphin, enkephalin, dynorphin)
• Serotonergic (5-HT1A, 5-HT3)
• Noradrenergic (α2 receptors)
• Chronic pain – microglial activation (P2X4, BDNF), astrocytic changes

Part II: Sleep Neurochemistry

• Wake-promoting systems – orexin/hypocretin (lateral hypothalamus), histamine (TMN), dopamine (VTA), norepinephrine (LC), acetylcholine (basal forebrain, PPT/LDT)
• NREM sleep – VLPO (GABA, galanin) inhibition of wake systems, adenosine (A1, A2A receptors)
• REM sleep – acetylcholine (PPT/LDT), GABA (vPAG, lateral LPT), glutamate
• Melatonin – pineal gland synthesis (AANAT, ASMT), MT1/MT2 receptors, circadian entrainment
• Homeostatic sleep drive – adenosine, prostaglandin D2, nitric oxide

Part III: Circadian Rhythms

• Suprachiasmatic nucleus (SCN) molecular clock – transcription-translation feedback loops
• Core loop: CLOCK/BMAL1 → Per (1-3) and Cry (1-2) → repression
• Stabilizing loops: REV-ERBα/β, RORα
• Photon input – melanopsin (ipRGCs) → retinohypothalamic tract → SCN
• Outputs – rhythmic expression of clock-controlled genes (Dbp, Tef, Hlf, Wee1)
• Peripheral clocks (liver, heart, adipose) and brain clocks
• Chronotype and chronodisruption (shift work, jet lag)

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Volume 9: Neuroimmunology and Neuroinflammation

Part I: Immune Cells in the CNS

• Microglia – origin (yolk sac), self-renewal, morphology, markers (IBA1, P2RY12, TMEM119, CX3CR1)
• Border-associated macrophages (BAMs) – meningeal, perivascular, choroid plexus
• Astrocytes – reactive astrogliosis (GFAP↑, vimentin↑, nestin↑), A1 (neurotoxic) vs. A2 (neuroprotective) phenotypes
• Infiltrating T cells, B cells, monocytes (in pathology)

Part II: Inflammatory Mediators

• Cytokines – IL-1β, IL-6, TNF-α, IL-10, TGF-β
• Chemokines – CCL2, CXCL10, CX3CL1 (fractalkine)
• Complement system – C1q, C3, C5, membrane attack complex (MAC)
• Prostaglandins (COX-1/2, PGE₂, PGD₂)
• Reactive oxygen and nitrogen species (NOX2, iNOS, MPO)

Part III: Neuroimmune Signaling Pathways

• Toll-like receptors (TLR2, TLR3, TLR4, TLR7, TLR9) – ligands (LPS, dsRNA, ssRNA, CpG DNA)
• NLRP3 inflammasome – activation (ATP, Aβ, α-synuclein, urate), caspase-1, IL-1β/IL-18
• NF-κB pathway in glia
• JAK/STAT pathway (IFN-γ, IL-6)

Part IV: Neuroimmune Disorders

• Multiple sclerosis (MS) – oligodendrocyte damage, demyelination, Th17 cells, B cells, oligoclonal bands
• Autoimmune encephalitis (anti-NMDA receptor, anti-LGI1, anti-GAD65)
• Neuromyelitis optica (NMO) – aquaporin-4 autoantibodies
• Microgliopathies (ALSP due to CSF1R mutations, Nasu-Hakola due to TREM2/DAP12)

Part V: Neuroinflammation in Disease

• Alzheimer’s – microglial TREM2, CD33, CR1, complement, NLRP3
• Parkinson’s – microglial activation, MHC-II upregulation, α-synuclein as DAMP
• Depression – microglial priming, kynurenine pathway, sickness behavior
• Traumatic brain injury (TBI) – diffuse axonal injury, chronic traumatic encephalopathy (CTE)

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Volume 10: Neurochemistry of Injury, Repair, and Regeneration

Part I: Acute Neural Injury

• Ischemic stroke – excitotoxicity (glutamate, NMDA), calcium overload, mitochondrial permeability transition (mPT), ROS, inflammation, apoptosis (caspase-3)
• Traumatic brain injury (TBI) – mechanical damage, diffuse axonal injury (β-APP accumulation), hemorrhage, edema
• Spinal cord injury (SCI) – primary and secondary injury, glial scar (chondroitin sulfate proteoglycans, CSPGs), myelin-associated inhibitors (Nogo-A, MAG, OMgp)

Part II: Axonal and Synaptic Degeneration

• Wallerian degeneration – SARM1 (NAD⁺ depletion), NMNAT2 protection
• Axonal transport defects – dynein/kinesin mutations, tauopathies
• Synaptic loss mechanisms – complement (C1q, C3) tagging, microglial pruning

Part III: Repair and Regeneration Mechanisms

• Growth cone collapse vs. regeneration – RhoA/ROCK pathway
• Intrinsic growth capacity – PTEN/mTOR, KLF family, SOCS3
• Neurotrophic support after injury (BDNF, GDNF, NGF, CNTF)
• Oligodendrocyte precursor cell (OPC) response to demyelination – differentiation failure in MS
• Stem cell niches in repair (SVZ, SGZ) – limited migration to injury sites

Part IV: Glial Scar and CSPGs

• Chondroitin sulfate proteoglycans (aggrecan, brevican, neurocan, versican)
• Chondroitinase ABC as therapeutic
• Astrocyte reactivity – GFAP, vimentin, nestin, STAT3 pathway

Part V: Biomaterials and Molecular Therapies

• Hydrogels for SCI repair (peptide amphiphiles, hyaluronic acid, Matrigel)
• Growth factor delivery (heparin-binding, slow-release microspheres)
• Gene therapy for regeneration (AAV-PTEN shRNA, AAV-SOCS3)
• CRISPR editing in injury models

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Volume 11: Emerging Technologies and Molecular Tools (2020–2026)

Part I: Optogenetics and Chemogenetics

• Optogenetic actuators – channelrhodopsins (ChR2, ChRmine, ChroME), halorhodopsin (NpHR), archaerhodopsin (Arch)
• Genetically encoded voltage indicators (GEVIs) – ArcLight, ASAP, Voltron
• Chemogenetics – DREADDs (hM3Dq, hM4Di, KORD, rM3Ds)
• Designer receptors and their ligands (clozapine-N-oxide, deschloroclozapine)

Part II: Genetically Encoded Biosensors

• Calcium indicators – GCaMP6, GCaMP7, GCaMP8 (fast kinetics), jGCaMP7
• Neurotransmitter sensors – GRAB sensors (dopamine, serotonin, norepinephrine, acetylcholine, adenosine), iGluSnFR, GABA-sensor, dLight
• Voltage sensors – ASAP, Voltron
• Metabolic sensors – ATP (ATeam, PercevalHR), lactate (Laconic), NADH (Peredox)

Part III: Proteomics and Metabolomics

• Quantitative proteomics (SILAC, TMT, LFQ) in synaptosomes, myelin, CSF
• Spatial proteomics (Deep Visual Proteomics, GeoMX)
• Metabolomics (LC-MS/MS, NMR) – neurotransmitter turnover, energy metabolites, lipidomics
• Post-translational modification mapping (phosphoproteomics, ubiquitinomics, acetylation)

Part IV: Single-Cell and Spatial Omics

• Single-cell RNA-seq (10x Genomics, SMART-seq) – neuronal subtypes, glial heterogeneity
• Single-nucleus RNA-seq (snRNA-seq) – archived human brain tissue
• Spatial transcriptomics (Visium, MERFISH, Xenium, CosMX)
• Single-cell ATAC-seq – chromatin accessibility in brain cells
• Multi-omics (RNA + protein, RNA + ATAC)

Part V: CRISPR and Gene Editing

• CRISPR-Cas9, Cas12, Cas13 (RNA editing)
• Base editing (ABE, CBE) – correction of point mutations
• Prime editing – versatile DNA editing
• Epigenome editing (CRISPRa, CRISPRi, dCas9-p300, dCas9-KRAB)
• In vivo delivery – AAV, LNP, virus-like particles (VLPs)

Part VI: Brain Organoids and Assembloids

• Cerebral organoids (Lancaster & Knoblich, 2013 – 2026 refinements)
• Region-specific organoids (midbrain, striatum, cerebellum, hippocampus)
• Vascularized organoids
• Assembloids (cortex–striatum, cortex–spinal cord, thalamus–cortex)
• Microelectrode array integration (MEA) for functional characterization

Part VII: In Vivo Neurochemistry

• Fiber photometry (GCaMP, GRAB sensors) – freely behaving animals
• Two-photon imaging with biosensors
• Fast-scan cyclic voltammetry (FSCV) with carbon-fiber electrodes
• Microdialysis coupled to LC-MS
• GRAB sensors in mice and rats (2020–2025 expansion)

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Volume 12: Translational Neurochemistry – Diagnostics, Therapeutics, and Future Directions

Part I: Neurochemical Biomarkers

• CSF biomarkers – Aβ42/40, p-tau181/217, t-tau (AD), neurofilament light (NfL) for neurodegeneration, glial fibrillary acidic protein (GFAP) for astrogliosis
• Blood biomarkers – plasma p-tau217, NfL, GFAP, exosomal α-synuclein
• Urine and saliva neurochemical markers (limited utility)
• PET tracers – amyloid (PiB, Florbetapir, Flutemetamol), tau (Flortaucipir, MK-6240), neuroinflammation (TSPO tracers: PBR28, DPA-714), dopamine (FDOPA, D2 receptor tracers)

Part II: Neurochemical Pharmacotherapy

• Alzheimer’s – cholinesterase inhibitors (donepezil, rivastigmine, galantamine), memantine (NMDA antagonist), aducanumab/lecanemab (anti-Aβ antibodies, 2021–2023 approvals)
• Parkinson’s – L-DOPA (aromatic amino acid decarboxylase with carbidopa), MAO-B inhibitors (selegiline, rasagiline), COMT inhibitors (entacapone), dopamine agonists (pramipexole, ropinirole), amantadine
• Depression – SSRIs (fluoxetine, sertraline), SNRIs (venlafaxine, duloxetine), ketamine/esketamine (2020–2026 expanded use), psilocybin (Phase III trials by 2026)
• Schizophrenia – dopamine D2 antagonists (haloperidol, risperidone, paliperidone), partial agonists (aripiprazole, brexpiprazole, cariprazine), M1/M4 muscarinic agonists (emraclidine – Phase III 2024–2026)
• Epilepsy – sodium channel blockers, GABAergic agents, SV2A modulators
• Multiple sclerosis – immunomodulators (interferon-β, glatiramer acetate, anti-CD20 mAbs, S1P modulators)

Part III: Gene and Cell Therapies

• AAV gene therapy – spinal muscular atrophy (Zolgensma – SMN1), AADC deficiency, giant axonal neuropathy, RPE65 deficiency
• Antisense oligonucleotides (ASOs) – nusinersen (SMA), tofersen (SOD1 ALS, 2023 accelerated approval)
• CRISPR therapies (in trials for Huntington’s, Leber congenital amaurosis by 2026)
• Induced pluripotent stem cell (iPSC) derived neurons for cell replacement (PD – dopamine neurons, phase I/II trials 2020–2026)

Part IV: Neurometabolic and Mitochondrial Disorders

• Mitochondrial diseases – Leigh syndrome, MELAS, MERRF, LHON
• Lysosomal storage disorders – Gaucher (glucocerebrosidase), Tay-Sachs (HexA), Niemann-Pick (NPC1), enzyme replacement therapy (ERT) and substrate reduction therapy (SRT)
• Peroxisomal disorders – adrenoleukodystrophy (ALD), Zellweger spectrum

Part V: Neurotoxicology

• Heavy metals – lead (Pb²⁺), mercury (MeHg), manganese (Mn²⁺)
• Pesticides – paraquat, rotenone (mitochondrial toxins, PD risk)
• Drugs of abuse neurotoxicity – methamphetamine, MDMA, alcohol (Wernicke–Korsakoff – thiamine deficiency)
• Chemotherapy-induced cognitive impairment (“chemobrain”) – oxidative stress, microglial activation
• Anesthetics – neurotoxicity in developing brain (GABA-A, NMDA)

Part VI: Future Directions (2026 and beyond)

• In vivo real-time neurotransmitter mapping (next-gen GRAB sensors, voltage imaging)
• Whole-brain molecular mapping (spatial omics at cellular resolution)
• Closed-loop neurochemical modulation (optogenetics + biosensor feedback)
• Digital neurochemistry – AI-predicted neurochemical dynamics
• Personalized neurochemistry – polygenic risk scores + metabolomics for psychiatric drug selection
• Brain-machine interfaces (BMI) with neurochemical sensing (e.g., dopamine-based BMI for paralysis)

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Spesialised Topics

• Disease
• Psychology
• Mental Disorder
• Psychiatry
• Neuropharmacology
• Clinical Neuroscience and Neurological Disorders
• Glial Biology
• Neuroimmunology
• Computational Neuroscience
• Key discoveries: first neurotransmitter isolation, receptor cloning, optogenetics, CRISPR
• FDA approvals: L-DOPA, SSRIs, anti-Aβ antibodies, gene therapies

Appendixes (across all volumes)

1. Glossary of neurochemical terms (500+ definitions)
2. Neurotransmitter synthesis pathways (full metabolic diagrams)
3. Receptor and ion channel tables (subunits, localization, agonists, antagonists, effectors)
4. Neurochemical methods reference (principles, strengths, limitations of each technique)
5. Commonly used neurochemical reagents and their targets (pharmacology tables)
6. Brain region–specific neurochemical profiles (neurotransmitter and receptor densities)
7. CSF and blood biomarker reference ranges for neurodegenerative diseases
8. Neurochemical animal models (transgenic lines, toxin models, viral vector tools)
9. Timeline of major neurochemistry discoveries (1884–2026)
10. Safety and ethics in human neurochemical research (in vivo microdialysis, biomarker studies, genetic testing)
11. Neurochemical databases and resources (Human Protein Atlas, BrainMap, Allen Brain Atlas, Gene Ontology)
12. Index (cross-referenced by molecule, pathway, disease, technique, and volume)

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