References

Galvan MA, Shramm PA, Bouajram R, Lappi DA, Ancheta LR (2019) A high efficacy selection method for transfected cells utilizing recombinant isolectin B4-saporin. Neuroscience 2019 Abstracts 794.10. Society for Neuroscience, Chicago, IL.

Summary: Transfection protocols often rely on the use of antibiotics for the selection of transfected cells and has become the accepted approach for in vitro research and therapeutic applications. Antibiotics have several shortcomings such as cost, continuous use, and harmful effects — even on the transfected cell population. In addition, selection pressures are often inefficient and fail to provide a population of cells that express the gene of interest (GOI) at high levels. We have used three separate GOI’s to select for solely high-expressing transfectants using targeted toxin selection pressure. Normal Rat Kidney Cells (KNRK) were individually transfected to express green fluorescent protein (GFP), melanopsin or the low-affinity nerve growth factor receptor (p75) using an innovative new transfection delivery vector called pGEI. The results from various assays were utilized to visually determine the expression rate and pattern of the targeted toxin selection method. Melanopsin and p75 — a photopigment and nerve growth factor, respectively — were of great interest to express in our transfected cells as a means to study their role in the development and function of neurons. The delivery vector, pGEI, removes resident Galalpha(1-3)Gal epitopes from non- human mammalian cell surfaces. This residue is the target of recombinant Isolectin B4 – Saporin (IB4-SAP), a selective targeted toxin. IB4-SAP is extremely potent, with an EC50 in the low picomolar range for alpha-D-galactopyranoside expressing cells in vitro. The cells with the highest expression of the inserted vector, and therefore the GOI, will have these residues removed. Those that fail to express the vector or do not express the vector in high enough amounts, will not have all the residues removed, and will be targeted and eliminated via IB4-SAP. This method of selection provides a means of purifying the highest- expressing transfected populations using a more cost-effective and time-saving approach.

Related Products: IB4-SAP (Cat. #IT-10)

Chew C, Sengelaub DR (2019) Exercise is neuroprotective following partial motoneuron depletion via androgen action at the target muscle. Neuroscience 2019 Abstracts 134.13. Society for Neuroscience, Chicago, IL.

Summary: We have previously demonstrated that partial depletion of motoneurons innervating the quadriceps muscles induces dendritic atrophy in remaining motoneurons. Furthermore, systemic treatment with supplemental androgens is neuroprotective, and dendritic atrophy following partial motoneuron depletion is attenuated. Blockade of the androgen receptor at the target muscle prevents the neuroprotective effects on motoneuron dendrites in rats treated with supplemental androgens. We have recently shown that exercise is also neuroprotective on motoneuron dendrites following partial motoneuron depletion, and circulating levels of androgens have previously been shown to increase following exercise. Together, these results suggest that exercise may be neuroprotective via androgen action at the muscle. In the present study, we examine whether blockade of androgen receptors at the target musculature would prevent the neuroprotective effects of exercise on dendrites following partial motoneuron depletion. Motoneurons innervating the vastus medialis muscle in adult male rats were selectively killed by intramuscular injection of cholera toxin-conjugated saporin. Simultaneously, some saporin-injected rats were given implants of the androgen receptor antagonist hydroxyflutamide, either directly at the quadriceps musculature or interscapularly as a systemic control. Following saporin injections, some animals were allowed free access to running wheels attached to their home cages. Four weeks later, motoneurons innervating the ipsilateral vastus lateralis muscle were labeled with cholera toxin-conjugated horseradish peroxidase, and dendritic arbors were reconstructed in three dimensions. Compared with untreated males, partial motoneuron depletion resulted in decreased dendritic length in remaining quadriceps motoneurons. Early data suggests that following partial motoneuron depletion, exercised males with androgen receptor blockade at the quadriceps show dendritic lengths that are significantly shorter than those of exercised males with no treatment, while dendritic lengths in exercised males with interscapular implants do not differ from those of exercised animals without implants. These findings suggest that exercise may be protective against dendritic atrophy via androgens binding at the target musculature.

Related Products: CTB-SAP (Cat. #IT-14)

Truckenbrod LM, Bumanglag AV, Chun E, Hernandez A, Federico QP, Maurer AP, Sloviter RS, Burke SN (2019) Targeted hippocampal GABA neuron ablation produces hippocampal sclerosis, epilepsy, and dissociable effects on the Morris water maze and object-place paired association tasks. Neuroscience 2019 Abstracts 158.03. Society for Neuroscience, Chicago, IL.

Summary: An epileptogenic role for hippocampal GABAergic dysfunction has recently been reported (Chun et al. 2019). Specifically, selective ablation of hippocampal GABA neurons by Stable Substance P-saporin (SSP-saporin) conjugate caused dorsal hippocampal sclerosis and chronic epilepsy, without involving convulsive status epilepticus or widespread brain injury. The current study assessed cognitive function in chronically epileptic SSP-saporin-treated rats and their vehicle-injected controls ~8 months following injection. First, rats completed the Morris Water Maze test of spatial learning and memory (Morris et al., 1982). Animals then underwent testing with the object-place paired association (OPPA) task, which requires the hippocampus as well as functional connectivity between the hippocampus and cortical areas (Jo and Lee, 2010; Hernandez et al., 2017), and then a simple object discrimination task. Interestingly, both controls and rats with dorsal hippocampal sclerosis and chronic epilepsy were able to learn the location of the hidden platform in the Morris Water Maze task and could also acquire a simple pair-wise object discrimination. However, epileptic rats with dorsal hippocampal sclerosis were significantly impaired on the OPPA task, which requires animals to integrate spatial location memory with a correct object choice and is a more sensitive measure of cognitive dysfunction (Hernandez et al., 2015). These data indicate that, similar to humans with medial temporal lobe epilepsy, selective hippocampal sclerosis and epilepsy in this model do not result in global cognitive decline. Rather, cognitive functions that require functional connectivity between the hippocampus and cortical areas are selectively affected.

Related Products: SSP-SAP (Cat. #IT-11)

ATS Poster of the Year Winner. Read the featured article in Targeting Trends.

See Also:

• Chun E et al. Targeted hippocampal GABA neuron ablation by stable substance P-saporin causes hippocampal sclerosis and chronic epilepsy in rats. Epilepsia 60(5):e52-e57, 2019.

Guyenet PG, Stornetta RL, Souza GMPR, Abbott SBG, Shi Y, Bayliss DA. (2019) The retrotrapezoid nucleus: Central chemoreceptor and regulator of breathing automaticity. Trends Neurosci 42(11):807-824. doi: 10.1016/j.tins.2019.09.002

Summary: This review describes the neurons of the retrotrapezoid nucleus (RTN), their transcriptome, developmental lineage, and anatomical projections. The authors also review their contribution to CO2 homeostasis and to the regulation of breathing automaticity during sleep and wake.

Usage: Local injection of SSP-SAP to kill RTN neurons.

Related Products: SSP-SAP (Cat. #IT-11)

Li J, Xiang X, Xu H, Shi Y (2019) Cilostazol promotes angiogenesis and increases cell proliferation after myocardial ischemia–reperfusion injury through a camp-dependent mechanism. Cardiovasc Eng Technol 10(4):638-647. doi: 10.1007/s13239-019-00435-0 PMID: 31625080

Usage: western

Related Products: Fibroblast Growth Factor Rabbit Polyclonal, mammalian (Cat. #AB-07)

Kucinski A, Phillips KB, Koshy Cherian A, Sarter M (2020) Rescuing the attentional performance of rats with cholinergic losses by the M1 positive allosteric modulator TAK-071. Psychopharmacology (Berl) 237(1):137-153. doi: 10.1007/s00213-019-05354-5 PMID: 31620809

Related Products: 192-IgG-SAP (Cat. #IT-01)

Avrampou K, Pryce KD, Ramakrishnan A, Sakloth F, Gaspari S, Serafini RA, Mitsi V, Polizu C, Swartz C, Ligas B, Richards A, Shen L, Carr FB, Zachariou V (2019) RGS4 maintains chronic pain symptoms in rodent models. J Neurosci 39(42):8291-8304. doi: 10.1523/JNEUROSCI.3154-18.2019 PMID: 31308097

Usage: western

Related Products: Metabotropic Glutamate Receptor 2 (mGluR2) Mouse Monoclonal (Cat. #AB-N32)

Wercberger R, Basbaum AI (2019) Spinal cord projection neurons: A superficial, and also deep, analysis. Curr Opin Physiol 11:109-115. doi: 10.1016/j.cophys.2019.10.002

Summary: Modern approaches to map complex neural circuits require knowledge of the molecular language that defines cell type specificity. However, with few exceptions, NK1R remains the marker consistently used to define projection neurons and even to interrogate their contribution to pain and itch (Mantyh et al.) The first of two studies demonstrating that SP-SAP-mediated ablation of dorsal horn NK1R-expressing neurons reduces injury-induced hyperalgesia. (Carstens et al.) In this paper SP-SAP-mediated ablation of dorsal horn NK1R-expressing neurons reduced pruritogen-evoked scratching.

Related Products: SSP-SAP (Cat. #IT-11)

See Also:

• Mantyh PW et al. Inhibition of hyperalgesia by ablation of lamina I spinal neurons expressing the substance P receptor. Science 278:275-279, 1997.
• Carstens EE et al. Dorsal horn neurons expressing NK-1 receptors mediate scratching in rats. Neuroreport 21:303-308, 2010.

Murillo-Rodríguez E, Millán-Aldaco D, Palomero-Rivero M, Morales-Lara D, Mechoulam R, Drucker-Colín R (2019) Cannabidiol partially blocks the excessive sleepiness in hypocretindeficient rats: Preliminary data. CNS Neurol Disord Drug Targets 18(9):705-712. doi: 10.2174/1871527318666191021143300

Objective: To determine whether the systemic injection of CBD (5 mg/kg, i.p.) would block the excessive sleepiness in a narcoleptic model.

Summary: Preliminary findings suggest that CBD might prevent sleepiness in narcolepsy.

Usage: Orexin-SAP (490 ng/0.5 μL, n= 10) was bilaterally injected into the LH of rats to eliminate HCRT leading to the establishment of narcoleptic-like behavior.

Related Products: Orexin-B-SAP (Cat. #IT-20)

Verkhratsky A, Parpura V, Rodriguez-Arellano J, Zorec R (2019) Astroglia in Alzheimer’s Disease. (eds. Verkhratsky A, Ho M, Zorec R, Parpura V). In: Advances in Experimental Medicine and Biology: Neuroglia in Neurodegenerative Diseases. 1175:273-324. Springer, Singapore. doi: 10.1007/978-981-13-9913-8_11

Summary: A review of the tools for creating animal models of Alzheimer’s Disease. 192-IgG-SAP binds selectively and irreversibly to low-affinity nerve growth factor receptor interrupting cholinergic neuronal protein synthesis was employed. Anti-DBH-SAP binds dopamine-β-hydroxylase, which is not only localized mainly in the cytosol, but also at the plasma membrane surface of noradrenergic neurons. Anti-DBH-SAP produced specific and dose-dependent depletions of locus coeruleus neurons, with no effects on other cholinergic, dopaminergic or serotonergic neuronal populations. The possibility to induce a partial or total noradrenergic loss (by varying the injected dose) makes this immunotoxic approach an ideal model to study events within the noradrenergic projection system, as they occur during age-related demise of locus coeruleus in humans.

Related Products: 192-IgG-SAP (Cat. #IT-01), Anti-DBH-SAP (Cat. #IT-03)