targeted-toxins

Donertas-Ayaz B, Caudle RM (2023) Locus coeruleus-noradrenergic modulation of trigeminal pain: Implications for trigeminal neuralgia and psychiatric comorbidities. Neurobiol Pain 13:100124. doi: 10.1016/j.ynpai.2023.100124 PMID: 36974102

Objective: To summarize the knowledge about the involvement of noradrenaline in acute and chronic trigeminal pain conditions and how the activity of the locus coeruleus (LC) noradrenergic neurons changes in response to acute and chronic pain conditions and how these changes might be involved in pain-related comorbidities including anxiety, depression, and sleep disturbance.

Summary: LC inhibition of nociceptive transmission in acute pain and in longterm neuropathic pain increases the tonic activity of LC-NA neurons. These changes may contribute to impaired descending pain modulation and pain-related comorbidities such as depression, anxiety, and sleep disorders.

Usage: Elimination of NA neurons via injection of anti-dopamine β-hydroxylase-saporin (Anti-DBH-SAP) into the lateral ventricle and trigeminal brainstem nuclei three weeks after infraorbital nerve injury attenuated mechanical allodynia

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Zaichenko MI, Philenko P, Sidorina V, Grigoryan GA (2023) Acute and chronic lipopolysaccharide-induced stress changes expression of proinflammatory cytokine genes in the rat brain region-specifically and affects learning and memory. Biochemistry Moscow 88:526-538. doi: 10.1134/S0006297923040089

Objective: Goal of the work was to conduct comparative analysis of the effects of acute and chronic lipopolysaccharide- induced stress on the behavior of rats in the Morris water maze test and on expression of mRNA of proinflammatory cytokines and BDNF in different brain structures.

Summary: Chronic stress, depression, and other neuropsychiatric disorders have been often associated with inflammation processes and activity of the brain immune system. In order to investigate association of neuroinflammation with such disorders the model of proinflammatory bacterial lipopolysaccharide intoxication was used. In the experiments with rats, acute lipopolysaccharide (LPS)-induced stress improved learning in the Morris water maze and caused substantial increase of the TNF-α and IL-1β mRNA concentrations in the hippocampus and amygdala, but not in the frontal lobe in comparison with the control animals. Hprt and Ywhaz genes were selected for use as molecular biology reference genes based on the analysis of the rat hippocampus transcriptome from the work done by Dobryakova, Y.V. et. al (2018) Intracerebroventricular administration of 192IgG-saporin alters expression of microglia-associated genes in the dorsal but not ventral hippocampus.

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

See Also:

• Dobryakova YV et al. Intracerebroventricular administration of 192IgG-saporin alters expression of microglia-associated genes in the dorsal but not ventral hippocampus. Front Mol Neurosci 10:429, 2018.

Myers B, Islam S, Gleber Netto FO, Debnath KC, Srivastava S, Xie T, Akhter S, Adebayo AA, Miller J, Lothumalia S, Sathiskumar HN, Amit M (2023) Targeting nociceptive and cholinergic nerves in irradiated oropharyngeal cancer model reveals novel mechanism for dysphagia. Cancer Neuroscience Symposium

Objective: Explore the hypothesis that modulation of cholinergic (CHAT+) and nociceptive (CGRP+) neurons correlate with improved dysphagia.

Summary: Oropharyngeal squamous cell carcinoma is one of the most common types of head and neck cancer. Treatment for OPSCC includes surgery, radiation therapy, chemotherapy, or a combination of therapies. Despite advances in treatment, dysphagia (difficulty swallowing) is still a major burden for patients with OPSCC. The study established a novel murine OPSCC model to explore the role of nerves in dysphagia with cholinergic (CHAT) and nociceptive (CGRP) neurons playing an important role in swallowing outcomes. Targeting CHAT and CGRP could be a novel strategy for OPSCC patients with dysphagia.

Usage: 500 ng of Anti-ChAT-SAP was injected into the trigeminal ganglion in mice.

Related Products: Anti-ChAT-SAP (Cat. #IT-42)

Iqbal Z, Lei Z, Ramkrishnan AS, Liu S, Hasan M, Akter M, Lam YY, Li Y (2023) Adrenergic signalling to astrocytes in anterior cingulate cortex contributes to pain-related aversive memory in rats. Commun Biol 6:10. doi: 10.1038/s42003-022-04405-6 PMID: 36604595

Objective: To identify the role of norepinephrine in colorectal distention (sub-threshold for acute pain) induced conditioned place avoidance and plasticity gene expression in the anterior cingulate cortex (ACC).

Summary: The findings suggest that projection-specific adrenergic astrocytic signaling in ACC is integral to system-wide neuromodulation in response to visceral stimuli and plays a key role in mediating pain-related aversion consolidation and memory formation.

Usage: 0.25 ug of Anti-DBH-SAP (1 μg/μl) was injected into each hemisphere of locus coeruleus (LC).

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Leanza G, Zorec R (2023) Towards astroglia-based noradrenergic hypothesis of Alzheimer’s disease. Function (Oxf) 4(1):zqac060., IT. doi: 10.1093/function/zqac060 PMID: 36590326

Summary: These results indicate a prominent role of NA-neurons vs. ACh neurons in impairments of working memory, relevant for AD, and are consistent with an astrocyte-specific metabolic impairment in a mouse model of intellectual disability.

Usage: Bilateral icv injection of 192-IgG-SAP and/or Anti-DBH-SAP

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

Maunze B (2022) Pituitary adenylate cylase-activating polypeptide receptor: Multiple signaling pathways involved in energy homeostasis. Marquette University Dissertations 1212. Thesis.

Objective: To determine the endogenous role of pituitary adenylate cyclase activating polypeptide (PACAP) in affecting the ventromedial nuclei (VMN) of the hypothalamus and its control of feeding and energy expenditure through the Type I PAC1 receptor (PAC1R).

Summary: VMN cells expressing PAC1 receptors in Male Sprague Dawley rats were knocked down via injection of Saporin or PACAP-SAP and trafficking also pharmacologically inhibited. This increased meal sizes, reduced total number of meals, and induced body weight gain. PACAP signaling replicates the effects of leptin administration in the VMN and appears to enable leptin regulation of energy homeostasis. Co-immunoprecipitation was used to show that VMN PAC1 and leptin receptors are found in the same cell, and they form an immunocomplex. Inhibiting downstream effectors of PACAP signaling, such as PKA and PKC, enhanced or prevented leptin signaling respectively. The current findings revealed that endogenous PACAP signaling in the VMN has a potent regulatory influence over both energy intake in the form of feeding, and energy output via thermogenesis and locomotor activity. Moreover, PACAP actions in the VMN share nearly identical secondary effects as with leptin administration in the same brain region suggesting that these two neuropeptides could functionally intersect.

Related Products: PACAP-SAP (Cat. #IT-84)

Fullerton E (2022) The impact of advanced age on morphine anti-hyperalgesia and the role of mu opioid receptor signaling in the periaqueductal gray of male and female rats. Georgia State University doi: 10.57709/30509896

Objective: To investigate the impact of advanced age on the antihyperalgesic effect of morphine, as well as its association with changes in μ-opioid receptor expression and binding in the rat midbrain Periaqueductal Gray (PAG) in both male and female rats.

Summary: This study examined the effects of advanced age on the antihyperalgesic properties of morphine and its relationship with mu-opioid receptor expression and binding in the rat midbrain Periaqueductal Gray (PAG). The findings revealed that advanced age attenuated the antihyperalgesic effect of morphine, accompanied by a decrease in mu-opioid receptor expression and binding in the PAG of both male and female rats, suggesting age-related alterations in opioid signaling that may contribute to reduced analgesic efficacy in older individuals.

Related Products: Dermorphin-SAP / MOR-SAP (Cat. #IT-12)

Hoffman S, Alvares D, Adeli K (2022) GLP-1 attenuates intestinal fat absorption and chylomicron production via vagal afferent nerves originating in the portal vein. Mol Metab 65:101590. doi: 10.1016/j.molmet.2022.101590 PMID: 36067913

Objective: To examine the effect of vagal GLP-1 signaling on intestinal fat absorption and lipoprotein production.

Summary: Selective deafferentation of GLP-1R-containing nodose neurons with GLP-1R (Exenatide)-SAP caused significant increases in postprandial (but not fasting) plasma TG, plasma cholesterol, and TRL TG following an olive oil gavage. Over a 2-week period, increased food consumption and elevated liver lipids were also observed.

Usage: GLP-1R-SAP or Blank-SAP was administered to Syrian golden hamsters (bilateral nodose ganglia; 1 µg/1 µl).

Related Products: Ex4-SAP (GLP-1-SAP) (Cat. #IT-90), Blank-SAP (Cat. #IT-21)

Silva AR (2022) Uncovering central and peripheral pain mechanisms in Alzheimer’s disease. King’s College London Thesis.

Objective: To investigate alterations within the nociceptive pathways, under neuropathic pain conditions.

Summary: The data suggest a disrupted opioidergic tone in TASTPM mice, which followed by peripheral nerve injury, is mediated by peripheral immune cells.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

See Also:

• Brightwell JJ et al. Noradrenergic neurons in the locus coeruleus contribute to neuropathic pain. Neuroscience 160:174-185, 2009.

Zhou XA, Ngiam G, Qian L, Sankorrakul K, Coulson EJ, Chuang KH (2022) The basal forebrain volume reduction detected by MRI does not necessarily link with the cholinergic neuronal loss in the Alzheimer’s disease mouse model. Neurobiol Aging 117:24-32. doi: 10.1016/j.neurobiolaging.2022.03.017 PMID: 35640461

Objective: Assess basal forebrain (BF) cholinergic neuron number by histological counts and compare with the volume measurements from an in vivo MRI Alzheimer’s disease (AD) mouse model.

Summary: Degeneration of cholinergic neurons in the BF contributes to cognitive impairment in AD. A decrease of BF volume measured by structural MRI is thought to represent loss of cholinergic neurons. As there are various types of neurons in the BF, whether this MRI measurement actually reflects the change of cholinergic neurons has not been verified. To test whether specific loss of cholinergic neurons results in BF reduction, the authors ablated cholinergic neurons in the Medial septum.

Usage: Lesions were made via injections of mu-p75-SAP (0.5 mg/ml) or control Rabbit-IgG-SAP (0.5 mg/mL) into ten-week-old female C57Bl/6J mice. However, there was no detectable change in MRI volume between lesioned and unlesioned mice. The results indicate that although loss of cholinergic neurons within the BF likely contribute to volume loss, this change in volume cannot be taken as a direct biomarker of cholinergic neuron number.

Related Products: mu p75-SAP (Cat. #IT-16), Rabbit IgG-SAP (Cat. #IT-35)