Loss of ATP-sensitive channel expression and function decreases opioid sensitivity in a mouse model of type 2 diabetes.
Cole FisherKayla JohnsonMadelyn MooreAmir SadratiJody L JanecekMelanie J GrahamAmanda H KleinPublished in: bioRxiv : the preprint server for biology (2023)
During diabetes, β-cell dysfunction due to loss of potassium channels sensitive to ATP, known as K ATP channels occurs progressively over time contributing to hyperglycemia. K ATP channels are additionally present in the central and peripheral nervous systems and are downstream targets of opioid receptor signaling. The aim of this study is to investigate if K ATP channel expression or activity in the nervous system changes in diabetic mice and if morphine antinociception changes in mice fed a high fat diet (HFD) for 16 weeks compared to controls. Mechanical thresholds were also monitored before and after administration of glyburide or nateglinide, K ATP channel antagonists, for four weeks. HFD mice have decreased antinociception to systemic morphine, which is exacerbated after systemic treatment with glyburide or nateglinide. HFD mice also have lower rotarod scores, decreased mobility in an open field test, and lower burrowing behavior compared to their control diet counterparts, which is unaffected by K ATP channel antagonist delivery. Expression of K ATP channel subunits, Kcnj11 (Kir6.2) and Abcc8 (SUR1), were decreased in the peripheral and central nervous system in HFD mice, which is significantly correlated with baseline paw withdrawal thresholds. Upregulation of SUR1 through an adenovirus delivered intrathecally increased morphine antinociception in HFD mice, whereas Kir6.2 upregulation improved morphine antinociception only marginally. Perspective: This article presents the potential link between K ATP channel function and neuropathy during diabetes. There is a need for increased knowledge in how diabetes affects structural and molecular changes in the nervous system to lead to the progression of chronic pain and sensory issues.
Keyphrases
- high fat diet
- type diabetes
- chronic pain
- insulin resistance
- poor prognosis
- high fat diet induced
- adipose tissue
- cardiovascular disease
- glycemic control
- mouse model
- pain management
- healthcare
- stem cells
- oxidative stress
- cell proliferation
- signaling pathway
- metabolic syndrome
- risk assessment
- weight loss
- single molecule
- cerebrospinal fluid
- human health