Epigenetics and Pain Research

i-Fect Used to Study Impacts

Our i-Fect siRNA, miRNA and shRNA Trasfection Kit was recently used to study the impact of G9a-specific siRNA (AGUAACGGGCAUCAAUGC) on Mu Opioid Receptors: Yuhao Zhang, Shao-Rui Chen, Geoffroy Laumet, Hong Chen and Hui-Lin Pan. Nerve Injury Diminishes Opioid Analgesia through Lysine Methyltransferase-Mediated Transcriptional Repression of µ-Opioid Receptors in Primary Sensory Neurons. First Published on February 25, 2016, doi: 10.1074/jbc.M115.711812... In some SNL rats, G9a-specific siRNA (4 µg) or the negative control siRNA was administered intrathecally. G9a-specific siRNA(AGUAACGGGCAUCAAUGC) or universal negative control siRNA (#SIC001, Sigma-Aldrich) was mixed with i-Fect (Neuromics, Edina, MN) to a final concentration of 400 mg/L for the intrathecal injections...

Figures: G9a knockdown with siRNA reverses the MOR expression in the DRG and the morphine analgesic effect diminished by nerve injury. (A,B) Quantitative PCR (A) and Western blotting (B) analyses show the mRNA and protein levels of MORs in the DRGs of sham and SNL rats treated with control or G9a-specific siRNA (n = 10 rats in each group). The ipsilateral L5 and L6 DRG tissues were removed 24 h after the last siRNA injection. The amount of MOR mRNA and protein was normalized to GAPDH in the same samples, and the mean value of MOR levels in sham control rats was considered to be 1. (C) Time course of the intrathecal morphine effects on the tactile and pressure withdrawal thresholds in sham and SNL rats treated with G9a-specific siRNA or negative control siRNA (n = 9 rats in each group). The withdrawal thresholds after the last siRNA injection were plotted as the baseline control (BL).


Summary: The findings provide new insight into the epigenetic mechanism regulating MOR expression in primary sensory neurons in neuropathic pain. This multidisciplinary approach provides conclusive evidence for G9a as a key chromatin regulator responsible for MOR downregulation in the DRG and the analgesic efficacy of opioids reduced by nerve injury. A better understanding of the epigenetic mechanisms underlying nerve injury-induced downregulation of MORs in primary sensory neurons could help improve the analgesic efficacy of opioids for treating chronic neuropathic pain. G9a inhibitors could be used to enhance the opioid analgesic effect and reduce opioid consumption in patients with chronic neuropathic pain.

Delivery of siRNA, miRNA, shRNA and Plasmids Guaranteed

Potent and Frequently Published Transfection Solutions


We have proven and frequently published transfection solutions. 
Powerful punch and versatility are now needed more than ever with the 
hyper growth in gene manipulation technologies like Sleeping Beauty^TM
and CRISPR-Cas9.

We have published examples of the use of our solutions for delivering siRNA, miRNA, 
shRNA and plasmids both in vitro and in vivo. here are some of your options.
i-Fect ™ -A novel cationic lipid formulation specifically 
designed for efficient delivery of 27mer DsiRNAs(dicer 
substrate small Interfering RNAs)& 21mer siRNAs (small interfering RNAs) in vitro and in vivo.
p-Fect™ -Designed to delivery plasmids, DNA or 
RNA to hard to transfect Cell Lines.

pn-Fect™ -The latest advance in transfection 
for primary neuronal cells. 
This unique reagent provides ultra-high plasmid DNA delivery 
efficiencies and low cytotoxicity compared to competitive reagents.
Here's a recent i-Fect Publication:
Liuming Jiang, Qun Wu , Tao Yang. Silencing of Id2 Alleviates 
Chronic Neuropathic Pain Following Chronic Constriction Injury.
Journal of Molecular Neuroscience\pp 1-7.First online: 15 January 2016
 

Figure: Knockdown of Id2 attenuated mechanical allodynia and thermal 

hyperalgesia in CCI rats. (a and b) PWT and PWL were measured 1 day before 

CCI and 1, 3, 7, and 14 days after intrathecal administration of shRNA-Id2.

If you are looking for transfection solutions, do not hesitate to contact me @ direct phone: 612-801-1007 or pshuster@neuromics.com. Thank you, Pete Shuster, CEO and Owner, Neuromics

Kv Channels and Acute to Chronic Pain Transistion

i-Fect ^TMis a Proven Tool for Gene Manipulation in Studying All Types of Pain

I previously posted on use of our i-Fect Transfection Kit to silence Kv Channels Receptors. This has enabled researchers to study the role of these receptors in vitro and in vivo (see:i-Fect™ Delivers Your siRNA Payload).

Sample Data

Figure: Figures. siRNA-mediated knockdown of Kv1.1 expression in thoracic DRG significantly increased gastric sensitivity in naive adult rats. (A) Western blots showed a significant decrease in Kv1.1 protein in thoracic DRG (T8–T12) after intrathecal treatment with Kv1.1 siRNA but not with control siRNA. siRNA treatment did not alter TrpV1 expression (n = 5 rats each; *P < .01 vs control siRNA). (B) Naive rats treated with Kv1.1 siRNA showed a significant increase in VMR to gastric distention (n = 5 rats each, compared with pretreatment baseline; *P < .05). (C) Treatment with control siRNA had no significant effect on gastric hypersensitivity. (D) Patch clamp recordings from freshly dissociated gastric DRG neurons from FD-like and PND 10 saline-treated littermate controls showed a significant decrease in rheobase in FD-like rats (*P < .05), and (E) a significant increase in the number of action potentials elicited by current injection at 3× the rheobase in gastric DRG neurons from FD-like rats (*P < .05). (F) Sample voltage vs time traces showing action potentials evoked at ×1, ×2, and ×3 rheobase. The patch clamp data were obtained from 16 cells from 5 PND 10 saline control rats and 19 cells from 5 FD-like rats

I am pleased to share with you a new reference detailing how research use i-Fect to optimize and deliver euchromatic histone-lysine N-methyltransferase-2 (G9a) siRNA. This brings the number of publications referencing use of our Transfection Kits to over 45: Geoffroy Laumet, Judit Garriga, Shao-Rui Chen, Yuhao Zhang, De-Pei Li, Trevor M Smith, Yingchun Dong, Jaroslav Jelinek, Matteo Cesaroni, Jean-Pierre Issa & Hui-Lin Pan G9a is essential for epigenetic silencing of K+channel genes in acute-to-chronic pain transition. Nature Neuroscience (2015) doi:10.1038/nn.4165.

The authors report: "Selective knockout of the gene encoding G9a in DRG neurons completely blocked K+ channel silencing and chronic pain development after nerve injury. Remarkably, RNA sequencing analysis revealed that G9a inhibition not only reactivated 40 of 42 silenced genes associated with K+ channels but also normalized 638 genes down- or upregulated by nerve injury."

I will continue to post here new and unique solutions and related referencing for our Gene Expression Analysis Tools.

Introducing Sleeping Beauty

New Technology for Gene Transfer From Delivery to Stable Expression
Neuromics has a successful track record of helping our clients delivery siRNA, miRNA, Plasmids and other oligos in vitro and in vivo with our Transfection Kits...But my vision with our cell based assay solutions has always been to provide engineered cells and plasmids modified to study your genes of interest. I am pleased to announce we are working with Smart Cell /B-MoGen Technologies to make this happen. We now can provide:

Gene Transfer and Expression Products Leveraging the Sleeping Beauty Technology

Images: B-MoGen Transposon exhibiting stable expression of five fluorescent genes. 

Advantages of Sleeping Beauty Transposon System:
· Delivery method is time and cost effective compared to lentiviral delivery.
· Increased cargo-capacity when compared to lentiviral delivery.
· Safest insertion profile of all gene transfer methods.
· Commonly integrated as a single copy.
Custom vector design and assembly, including multi-gene (up to 6) vectors.
We are in the process of formulating standard offerings. In the meantime, I am positioned to offer favorable pricing and terms to early adopters of our Sleeping Beauty Solutions. Please contact me directly pshuster@neuromics.com or 612-801-1007. We can together determine your needs and desired outcomes and provide a statement of work with pricing, project milestones and delivery.

Silencing Cytokines in-vivo with i-Fect

Knocking Down Cytokines to Study Pain Response

We have many unique applications published by researchers using our Transfection Kits in vitro and in vivo. Here researchers simultaneously silence 3 immune/inflammatory response cytokines in vivo: Byung Moon Choi, Soo Han Lee, Sang Mee An, Do Yang Park, Gwan Woo Lee, and Gyu-Jeong Noh. The time-course and RNA interference of TNF-α, IL-6, and IL-1β expression on neuropathic pain induced by L5 spinal nerve transection in rats. Korean J Anesthesiol. 2015 Apr;68(2):159-169. English. Published online March 30, 2015. http://dx.doi.org/10.4097/kjae.2015.68.2.159.

Protocol: RNAs were administered as described, with modifications [11]. A cocktail of siRNA simultaneously targeting TNF-α (Silencer® Select siRNA; s128522, Ambion, Austin, TX, USA), IL-6 (Silencer® Select siRNA; s217844, Ambion, Austin, TX, USA) and IL-1b (Silencer® Select siRNA; s127941, Ambion, Austin, TX, USA), as well as a control siRNA (Silencer® Negative Control #1 siRNA; Cat #4635, Ambion, Austin, TX, USA), were prepared immediately prior to administration by mixing the RNA (200 µM) with the transfection reagent, i-Fect™ (Neuromics, Minneapolis, MN, USA), in a ratio of 1 : 5 (w : v). At this ratio, the final RNA/lipid complex concentration was 2 µg in 5 µl for each cytokine siRNA and 6 µg in 15 µl for the control siRNA. The cytokine siRNAs were combined and they and the control siRNA (15 µl each) were delivered to the lumbar region of the spinal cord via the intrathecal catheters. Injections were given daily on 5 consecutive days (-1, 0, 1, 2, 3 d after L5 SNT.

The changes in mechanically induced allodynia and hyperalgesia in the rats surviving for 6 d after SNT are shown in figure. Allodynia and hyperalgesia were lower in the COCK group than in the CON group by 2 d after SNT (P < 0.05) and the difference was maintained for the duration of the experiment.

Figure: The time course of mechanical allodynia (A) and hyperalgesia (B) in the ipsilateral hind paw of rats undergoing L5 spinal nerve transection (SNT) after the administration of control siRNA (CON group) or a cocktail of small interfering RNAs (siRNA) targeting TNF-α, IL-6 and IL1-β (COCK group). The data on the rats surviving for 6 d after SNT are expressed as mean ± SE. -1: 1 d prior to SNT, 0: the day of L5 SNT, 1, 2, 4 and 6: 1, 2, 4 and 6 d after L5 SNT. *P < 0.05 vs. CON group at each time point. MPE: maximal possible effect. The cut-off values for mechanical allodynia and hyperalgesia are 30 g and 250 g, respectively.

We will continue to post new applications and methods published by researchers using our Transfection Kits.

EPO Protects Against Cerebral Ischemia

Neuromics' i-Fect ^TM used to Modulate phospho-Connexin 43

In this study data suggest the protective effects of EPO on NUV injuries are highly associated with the increase of p-Cx43, which improves GJIC to reduce neurotoxic substances: Ziyi Zhoua, Xiaobai Weib, Jun Xiang, Junpeng Gao, Lixin Wang, Jinsong You, Yefeng Cai , Dingfang Caid. Protection of erythropoietin against ischemic neurovascular unit injuries through the effects of connexin43. Biochemical and Biophysical Research Communications. doi:10.1016/j.bbrc.2015.02...The strands were incubated at 90°C for 5 min and then at 37°C for 1 h. SiRNA was prepared immediately before administration by mixing the RNA solution (1 μg/μl in annealing buffer) with the transfection reagent i-Fect (v/v: 1/3; Neuromics, Edina, MN, USA) to a final siRNA ...

Highlights
•EPO has protective effects on ischemic NVU injuries.
•EPO up-regulates phosphorylation of Cx43, not total Cx43.
•EPO's protective effects on NUV injuries are p-Cx43-GJIC dependent.

HDAC2 and Anxiety in Alcoholism

The Impact of HDAC2 Gene Expression on Anxiety

Our i-Fect Transfection Kit continues to be a potent tool for testing the impact of altered gene expression on behavior. see: SACHIN MOONAT. The Role of Amygdaloid Chromatin and Synaptic Remodeling in Anxiety and Alcoholism. THESIS Submitted as partial fulfillment of the requirements for the degree of Doctor of Philosophy in Neuroscience in the Graduate College of the University of Illinois at Chicago, 2014.

The author hypothesized that increased HDAC2 would have a positive impact on anxiety in alchohol preferring (P) rats. Specifically, HDAC2-induced histone modifications in the amygdala may play a role in the regulation of synaptic plasticity that may underlie the behavioral phenotypes of P rats. Furthermore, it could be possible that exogenous manipulation of HDAC2 levels in the amygdala may have an effect on anxiety-like behaviors and alcohol preference in P rats.

Figure 1. Chromatin remodeling via histone acetylation and DNA methylation regulates gene transcription associated with changes in synaptic plasticity. During gene transcriptional processes, the chromatin structure associated with DNA to be transcribed is in a relaxed chromatin conformation due to hyperacetylation of histone proteins and hypomethylation of DNA, which allows access to transcriptional machinery. This relaxed chromatin structure results in increased gene transcription, which in neurons may cause increased expression of synaptically active proteins that result in the positive modulation of synaptic plasticity, such as increased dendritic spine density (DSD). DNA methyltransferase (DNMT) methylates DNA at CpG islands, leading to hypermethylated DNA and recruiting of methyl-CpG binding domain protein (MBD) complexes which block binding of transcriptional machinery. The MBD complex can in turn recruit histone deactylases (HDAC) which remove acetyl groups from histone proteins resulting in chromatin condensation thereby decreasing gene transcription. HDACs and histone acetyltransferases (HAT) control the histone acetylation profile, such that HDACs remove acetyl groups and HATs add acetyl groups to histone proteins. In this manner, increased HDAC expression results in hypoacetylation of histones leading to a condensed chromatin structure. Chromatin condensation resulting from HDAC-induced histone deacetylation or DNMT-induced DNA methylation causes reduced gene transcription. In neuronal cells, the reduction in gene transcription may be associated with decreased expression of synaptically active proteins and negative modulation of synaptic plasticity, such as reduced DSD. Treatment with DNMT inhibitors or HDAC inhibitors may block these enzymatic processes and return chromatin to a relaxed state, resulting in increased gene transcription and synaptic plasticity (Moonat and Pandey, 2012).

Methods: P rats that had been previously cannulated for delivery of solutions directly into the CeA were infused with either HDAC2 siRNA, control siRNA or vehicle. The siRNAs were dissolved in iFect solution (Neuromics, Edina, MN), a cationic lipid-based transfection solution, such that the final concentration of the solution was 2 µg/µL. The sequence of the HDAC2 siRNA was as follows: 5’-CAAGUUUCUACGAUCAACATT-3’; 5’- UAUUGAUCGUAGAAACUUGAT-3’. Some of the HDAC2 siRNA (Qiagen, Valencia, CA) had been modified to include a 5’ Alexa Fluor-488 fluorescent probe in order to determine the transfection efficiency and cellular localization of transfection. The control siRNA used was the AllStars Negative Control siRNA (Qiagen), which shows no homology to any known mammalian gene. To prepare the vehicle, RNase-free water was dissolved in the iFect solution in place of any siRNA. The solutions (0.5 µL) were infused bilaterally into the CeA of P rats using an automatic infusion pump which resulted in a dose of 1 µg of siRNA per side. The automatic pump was attached to a microdialysis probe which seated in the guide cannula and extended 3 mm past the tip of the cannula into the CeA.

For the experiments which looked at the anxiolytic effect of HDAC2 siRNA infusion, P rats were infused with either HDAC2 siRNA, control siRNA or vehicle at the end of the light cycle. 16 hours after the infusion, the rats were tested for anxiety-like behaviors. Immediately following behavioral testing, rats were anaesthetized and brains were collected for further analysis. For the voluntary drinking experiment, P rats were infused with either HDAC2 siRNA or vehicle when the bottles were changed following the third day of 9% ethanol exposure. The rats continued to be monitored for the intake of 9% ethanol for 7 days following the infusion. After the final day of voluntary drinking, the rats were anaesthetized for collection of brains and blood to confirm the cannula position and the blood alcohol levels, respectively.

Figure. The effects of HDAC2 siRNA Infusion into the CeA of P rats on voluntary ethanol consumption as measured by the two-bottle free choice paradigm. Monitoring the voluntary ethanol consumption of alcohol-preferring (P) rats via the two bottle free choice paradigm following infusion of vehicle or histone deacetylase isoform 2 (HDAC2) siRNA into the central amygdala (CeA) demonstrates that high HDAC2 levels may mediate the high alcohol drinking behaviors of P rats. P rats were given access to water and 7% ethanol followed by water and 9% ethanol. On the sixth day of ethanol access P rats received infusion of vehicle or HDAC2 siRNA and consumption of water and 9% ethanol were monitored for sevnfusion. Total fluid intake did not significantly differ between the groups. Values are represented as the mean ± SEM of the ethanol consumption (g / kg / day) and total fluid intake (mL) plotted daily for n=6 rats per treatment group. *Significantly different between the groups.

This data suggest reduction of HDAC2 levels in the CeA leads to reduced DSD associated with a reduction in anxiety-like behaviors and alcohol preference in P rats and could prove to have therapeutic value.