Acupuncture Reduces Hypertrophy and Cardiac Fibrosis, and Improves Heart Function in Mice with Diabetic Cardiomyopathy
CARDIOVASCULAR DRUGS AND THERAPY
Authors: Ye, Yumei; Birnbaum, Yochai; Widen, Steven G.; Zhang, Zhaohui; Zhu, Shipeng; Bajaj, Mandeep; Chen, Huan
Abstract
Purpose To assess the effects of electro-acupuncture (EA) on glycemic control, myocardial inflammation, and the progression of diabetic cardiomyopathy in mice with type 2 diabetes. Methods Db/Db mice received EA at PC6+ST36 (DM-Acu), non-acupoint simulation (DM-Sham), or no treatment (DM). EA was applied for 30 min per day, 5 days a week for 4 weeks. Heart function was assessed by echocardiography. Myocardium was assessed by RT-PCR, immunoblotting, and histology. Serum TNF-alpha, IL-1 alpha, IL-1 beta, IL-6, and IL-8 were measured. Results DM-Acu, but not DM-Sham, reduced fasting blood glucose without affecting body weight. DM decreased systolic function. DM-Acu, but not DM-Sham, attenuated the decrease in systolic function. Heart weight was significantly smaller in the DM-Acu than in the DM and DM-Sham groups. Percent fibrosis and apoptosis were reduced in the DM-Acu, but not the DM-Sham, group. Serum levels of IL-1 alpha, IL-1 beta, IL-6, IL-8, ICAM-1, MCP-1, and TNF-alpha were significantly lower in the DM-Acu than in the DM or DM-Sham groups. Protein levels of P-Akt and P-AMPK and mRNA levels of phosphoinositide-3-kinase regulatory subunit 6 (PIK3r6) were significantly higher in the DM-Acu group. Myocardial mRNA and protein levels of insulin-like growth factor 1 receptor (IGF1R) were significantly lower in the DM and DM-Sham groups compared with the DM-Acu group. Conclusions EA reduced serum glucose; prevented DM-induced hypertrophy and deterioration of systolic function, inflammation, and fibrosis; and restored IGF1R, P-Akt, and P-AMPK levels in mice with type 2 diabetes mellitus.
Loss of IGF1R in Human Astrocytes Alters Complex I Activity and Support for Neurons
NEUROSCIENCE
Authors: Ratcliffe, Laura E.; Villasenor, Irina Vazquez; Jennings, Luke; Heath, Paul R.; Mortiboys, Heather; Schwartzentruber, Aurelie; Karyka, Evangelia; Simpson, Julie E.; Ince, Paul G.; Garwood, Claire J.; Wharton, Stephen B.
Abstract
The insulin/insulin-like growth factor 1 (IGF1) signaling pathways are implicated in longevity and in progression of Alzheimer's disease. Previously, we showed that insulin-like growth factor 1 receptor (IGF1R) and downstream signaling transcripts are reduced in astrocytes in human brain with progression of Alzheimer's neuropathology and developed a model of IGF1 signaling impairment in human astrocytes using an IGF1R-specific monoclonal antibody, MAB391. Here, we have established a novel human astrocyte-neuron co-culture system to determine whether loss of astrocytic IGF1R affects their support for neurons. Astrocyte-neuron co-cultures were developed using human primary astrocytes and differentiated Lund Human Mesencephalic Cells (LUHMES). Neurite outgrowth assays, performed to measure astrocytic support for neurons, showed astrocytes provided contact-mediated support for neurite outgrowth. Loss of IGF1R did not affect neurite outgrowth under control conditions but when challenged with hydrogen peroxide IGF1R-impaired astrocytes were less able to protect LUHMES. To determine how loss of IGF1R affects neuronal support MAB391-treated astrocytes were FACS sorted from GFP-LUHMES and their transcriptomic profile was investigated using microarrays. Changes in transcripts involved in astrocyte energy metabolism were identified, particularly NDUFA2 and NDUFB6, which are related to complex I assembly. Loss of complex I activity in MAB391-treated astrocytes validated these findings. In conclusion, reduced IGF1 signaling in astrocytes impairs their support for neurons under conditions of stress and this is associated with defects in the mitochondrial respiratory chain in astrocytes. (C) 2018 The Authors. Published by Elsevier Ltd on behalf of IBRO.