scholarly journals High-Fat Diet Causes Mitochondrial Dysfunction as a Result of Impaired ADP Sensitivity

Diabetes ◽  
2018 ◽  
Vol 67 (11) ◽  
pp. 2199-2205 ◽  
Author(s):  
Paula M. Miotto ◽  
Paul J. LeBlanc ◽  
Graham P. Holloway
2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C Bo-Htay ◽  
T Shwe ◽  
S Palee ◽  
T Pattarasakulchai ◽  
K Shinlapawittayatorn ◽  
...  

Abstract Background D-galactose (D-gal) induced ageing has been shown to exacerbate left ventricular (LV) dysfunction via worsening of apoptosis and mitochondrial dysfunction in the heart of obese rats. Hyperbaric oxygen therapy (HBOT) has been demonstrated to exert anti-inflammatory and anti-apoptotic effects in multiple neurological disorders. However, the cardioprotective effect of HBOT on inflammation, apoptosis, LV and mitochondrial functions in D-gal induced ageing rats in the presence of obese-insulin resistant condition has never been investigated. Purpose We sought to determine the effect of HBOT on inflammation, apoptosis, mitochondrial functions and LV function in pre-diabetic rats with D-gal induced ageing. We hypothesized that HBOT attenuates D-gal induced cardiac mitochondrial dysfunctions and reduces inflammation and apoptosis, leading to improved LV function in pre-diabetic rats. Methods Forty-eight male Wistar rats were fed with either normal diet or high-fat diet for 12 weeks. Then, rats were treated with either vehicle groups (0.9% NSS, subcutaneous injection (SC)) or D-gal groups (150 mg/kg/day, SC) for 8 weeks. At week 21, rats in each group were equally divided into 6 sub-groups: normal diet fed rats treated with vehicle (NDV) sham, normal diet fed rats treated with D-gal (NDDg) sham, high fat diet fed rats treated with D-gal (HFDg) sham, high fat diet fed rats treated with vehicle (HFV) + HBOT, NDDg + HBOT and HFDg + HBOT. Sham treated rats were given normal concentration of O2 (flow rate of 80 L/min, 1 ATA for 60 minutes), whereas HBOT treated rats were subjected to 100% O2 (flow rate of 250 L/min, 2 ATA for 60 minutes), given once daily for 2 weeks. Results Under obese-insulin resistant condition, D-gal-induced ageing aggravated LV dysfunction (Fig 1A) and impaired cardiac mitochondrial function, increased cardiac inflammatory and apoptotic markers (Fig 1B). HBOT markedly reduced cardiac TNF-α level and TUNEL positive apoptotic cells, and improved cardiac mitochondrial function as indicated by decreased mitochondrial ROS production, mitochondrial depolarization and mitochondrial swelling, resulting in the restoration of the normal LV function in HFV and NDDg rats, compared to sham NDDg rats. In addition, in HFDg treated rats, HBOT attenuated cardiac TNF-α level, TUNEL positive apoptotic cells and cardiac mitochondrial dysfunction, compared to sham HFDg rats, leading to improved cardiac function as indicated by increased %LV ejection fraction (LVEF) (Figure 1). Conclusion HBOT efficiently alleviates D-gal-induced-age-related LV dysfunction through mitigating inflammation, apoptosis and mitochondrial dysfunction in pre-diabetic rats. Figure 1 Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): 1. The National Science and Technology Development Agency Thailand, 2. Thailand Research Fund Grants


2020 ◽  
Vol 244 (2) ◽  
pp. 353-367 ◽  
Author(s):  
Jiali Liu ◽  
Yue Li ◽  
Xiaoyan Zhou ◽  
Xi Zhang ◽  
Hao Meng ◽  
...  

High-fat diet (HFD) not only induces insulin resistance in liver, but also causes autophagic imbalance and metabolic disorders, increases chronic inflammatory response and induces mitochondrial dysfunction. Calcium/calmodulin-dependent protein kinase IV (CaMKIV) has recently emerged as an important regulator of glucose metabolism and skeletal muscle insulin action. Its activation has been involved in the improvement of hepatic and adipose insulin action. But the underlying mechanism is not fully understood. In the present study, we aimed to address the direct effects of CaMKIV in vivo and to evaluate the potential interaction of impaired insulin sensitivity and autophagic disorders in hepatic insulin resistance. Our results indicated obese mice receiving CaMKIV showed decreased blood glucose and serum insulin and improved insulin sensitivity as well as increased glucose tolerance compared with vehicle injection. Meanwhile, defective hepatic autophagy activity, impaired insulin signaling, increased inflammatory response and mitochondrial dysfunction in liver tissues which are induced by high-fat diet were also effectively alleviated by injection of CaMKIV. Consistent with these results, the addition of CaMKIV to the culture medium of BNL cl.2 hepatocytes markedly restored palmitate-induced hepatic insulin resistance and autophagic imbalance. These effects were nullified by blockade of cyclic AMP response element-binding protein (CREB), indicating the causative role of CREB in action of CaMKIV. Our findings suggested that CaMKIV restores hepatic autophagic imbalance and improves impaired insulin sensitivity via phosphorylated CREB signaling pathway, which may offer novel opportunities for treatment of obesity and diabetes.


Antioxidants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1201
Author(s):  
Claudio Pirozzi ◽  
Adriano Lama ◽  
Chiara Annunziata ◽  
Gina Cavaliere ◽  
Clara Ruiz-Fernandez ◽  
...  

Lines of evidence have shown the embryogenic and transgenerational impact of bisphenol A (BPA), an endocrine-disrupting chemical, on immune-metabolic alterations, inflammation, and oxidative stress, while BPA toxic effects in adult obese mice are still overlooked. Here, we evaluate BPA’s worsening effect on several hepatic maladaptive processes associated to high-fat diet (HFD)-induced obesity in mice. After 12 weeks HFD feeding, C57Bl/6J male mice were exposed daily to BPA (50 μg/kg per os) along with HFD for 3 weeks. Glucose tolerance and lipid metabolism were examined in serum and/or liver. Hepatic oxidative damage (reactive oxygen species, malondialdehyde, antioxidant enzymes), and mitochondrial respiratory capacity were evaluated. Moreover, liver damage progression and inflammatory/immune response were determined by histological and molecular analysis. BPA amplified HFD-induced alteration of key factors involved in glucose and lipid metabolism, liver triglycerides accumulation, and worsened mitochondrial dysfunction by increasing oxidative stress and reducing antioxidant defense. The exacerbation by BPA of hepatic immune-metabolic dysfunction induced by HFD was shown by increased toll-like receptor-4 and its downstream pathways (i.e., NF-kB and NLRP3 inflammasome) amplifying inflammatory cytokine transcription and promoting fibrosis progression. This study evidences that BPA exposure represents an additional risk factor for the progression of fatty liver diseases strictly related to the cross-talk between oxidative stress and immune-metabolic impairment due to obesity.


2018 ◽  
Vol 234 (5) ◽  
pp. 7510-7523 ◽  
Author(s):  
Dengqiu Xu ◽  
Zhenzhou Jiang ◽  
Zeren Sun ◽  
Lu Wang ◽  
Guolin Zhao ◽  
...  

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