Monday, September 16, 2019

High Fat and Diet Induced Obesity

i-FectTM Delivers Again!

Research shows that rats and humans on a high-fat diet (HFD) are less sensitive to satiety signals known to act via vagal afferent pathways. Impaired vagal afferent responsiveness to both gastric satiety hormones (CCK and leptin) and mechanical stimulation raises the possibility that changes in electrophysiological properties may be the underlying mechanism responsible for impaired vagal responsiveness to a wide variety of satiety signals.

Potassium channels play a central role. To demonstrate this researchers used our i-Fect siRNA Transfection Kit to silence TRESK and TASK1 to understand there impact on HFD on vagal responsiveness. Gintautas Grabauskas, Xiaoyin Wu, ShiYi Zhou, JiYao Li, Jun Gao, and Chung Owyang. (2019). High-fat diet–induced vagal afferent dysfunction via upregulation of 2-pore domain potassium TRESK channel. JCI Insight. https://doi.org/10.1172/jci.insight.130402.

Images: (A) Representative recordings of NG neuron responses to intra–superior pancreaticoduodenal artery infusions of CCK-8 (60 pmol/kg) and leptin (60 pmol/kg) in LFD-fed or HFD-fed rats and transfected with control siRNA or TRESK siRNA. Note that CCK-8 generated significantly fewer action potentials in HFD-fed rats compared with those fed an LFD. (B) Summary histograms showing single-unit discharges in response to CCK-8 in rats given an LFD and transfected with control siRNA (n = 11) or TRESK siRNA (n = 6), HFD + control siRNA (n = 12), and HFD treated with TRESK siRNA (n = 10). Data are represented as mean ± SEM. One-way ANOVA with Bonferroni’s test, *P < 0.05 vs. LFD + control siRNA; #P < 0.05 vs. HFD + control siRNA. (C) Summary histogram showing single-unit discharges in response to leptin in rats given an LFD and transfected with control siRNA (n = 11) and TRESK siRNA (n = 5), HFD (n = 12), and HFD treated with TRESK siRNA (n = 10). Data are represented as mean ± SEM. One-way ANOVA with Bonferroni’s test, *P less than 0.05 vs. LFD + control siRNA; #P less than 0.05 vs. HFD + control siRNA. (D) Summary histogram showing CCK-AR and ObR expression in vagal sensory ganglia from LFD- and HFD-fed rats were not significantly different. HPRT was used as a loading control. Data are represented as mean ± SEM. CCK-8, cholecystokinin-8.

Following 2 weeks of high-fat feeding, there was a significant upregulation of TRESK and a modest increase in TASK1 channels in the NG. Silencing studies indicate that the upregulation by TRESK channels is mainly responsible for a global decrease in excitability of vagal sensory neurons, which in turn dampens the response to satiety signals, such as CCK and leptin. 

This make TRESK a potential therapeutic target for treating Obesity.


Saturday, September 07, 2019

Potent FBS-Only $289/500 ml.

Hurry!
We our a bit over stocked in FBS. In order to fix, we are offering it for $289/500 ml. This offer is only good through September 15, 2019 so you will need to hurry.

Primary mouse vascular smooth muscle cells stained with smooth muscle alpha actin in DMEM with Neuromics 10% FBS. Data courtesy of Deng-Fu Guo, University of Iowa.

Note: We test each lot of FBS on our primary human cell cultures enabling us to choose lots yielding the best results...Testimonial: "We have used the FBS from Neuromics in feeding media for primary mouse astrocytes as well as for some cell lines. Your product is good and we plan to continue using it.” - Svetlana Vidensky, MS, Senior Research Specialist in Dr. Jeffrey Rothstein lab, Department of Neurology, Johns Hopkins University. Questions?  Contact Rose at rose@neuromics.com or 952-374-6161