Effect of Dietary Fats and Fatty Acids on the Liver Lipid Accumulation Induced by Feeding a Protein-repletion Diet Containing Fructose to Protein-depleted Rats

Recent evidence has highlighted that fat accumulation, particularly abdominal fat distribution, is strongly associated with metabolic disturbance. It is also well-recognized that the metabolic responses to variations in macronutrients intake can affect body composition. Previous studies suggest that the quality of dietary fats can be considered as the main determinant of body-fat deposition, fat distribution, and body composition without altering the total body weight; however, the effects of dietary fats on body composition have controversial results. There is substantial evidence to suggest that saturated fatty acids are more obesogen than unsaturated fatty acids, and with the exception of some isomers like conjugate linoleic acid, most dietary trans fatty acids are adiposity enhancers, but there is no consensus on it yet. On the other hand, there is little evidence to indicate that higher intake of the n-3 and the n-6 polyunsaturated fatty acids can be beneficial in attenuating adiposity, and the effect of monounsaturated fatty acids on body composition is contradictory. Accordingly, the content of this review summarizes the current body of knowledge on the potential effects of the different types of dietary fatty acids on body composition and adiposity. It also refers to the putative mechanisms underlying this association and reflects on the controversy of this topic.

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Aqueous Extract of Pepino Leaves Ameliorates Palmitic Acid-Induced Hepatocellular Lipotoxicity via Inhibition of Endoplasmic Reticulum Stress and Apoptosis

Antioxidants ◽

10.3390/antiox10060903 ◽

2021 ◽

Vol 10 (6) ◽

pp. 903

Author(s):

Jen-Ying Hsu ◽

Hui-Hsuan Lin ◽

Charng-Cherng Chyau ◽

Zhi-Hong Wang ◽

Jing-Hsien Chen

Keyword(s):

Fatty Acid ◽

Palmitic Acid ◽

Er Stress ◽

Lipid Accumulation ◽

Hepg2 Cells ◽

Target Genes ◽

Liver Lipid ◽

Antioxidant Response ◽

Long Chain Fatty Acid ◽

Nrf2 Expression

Saturated fatty acid is one of the important nutrients, but contributes to lipotoxicity in the liver, causing hepatic steatosis. Aqueous pepino leaf extract (AEPL) in the previous study revealed alleviated liver lipid accumulation in metabolic syndrome mice. The study aimed to investigate the mechanism of AEPL on saturated long-chain fatty acid-induced lipotoxicity in HepG2 cells. Moreover, the phytochemical composition of AEPL was identified in the present study. HepG2 cells treated with palmitic acid (PA) were used for exploring the effect of AEPL on lipid accumulation, apoptosis, ER stress, and antioxidant response. The chemical composition of AEPL was analyzed by HPLC-ESI-MS/MS. AEPL treatment reduced PA-induced ROS production and lipid accumulation. Further molecular results revealed that AEPL restored cytochrome c in mitochondria and decreased caspase 3 activity to cease apoptosis. In addition, AEPL in PA-stressed HepG2 cells significantly reduced the ER stress and suppressed SREBP-1 activation for decreasing lipogenesis. For defending PA-induced oxidative stress, AEPL promoted Nrf2 expression and its target genes, SOD1 and GPX3, expressions. The present study suggested that AEPL protected from PA-induced lipotoxicity through reducing ER stress, increasing antioxidant ability, and inhibiting apoptosis. The efficacy of AEPL on lipotoxicity was probably concerned with kaempferol and isorhamnetin derived compounds.

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Enhanced lipid accumulation in Metschnikowia pulcherrima using volatile fatty acids under non-sterile repeated batch cultivation

International Biodeterioration & Biodegradation ◽

10.1016/j.ibiod.2021.105256 ◽

2021 ◽

Vol 163 ◽

pp. 105256

Author(s):

Qian Li ◽

Danyang Wang ◽

Xiaolei Liu ◽

Anjie Li ◽

Kartik Chandran

Keyword(s):

Fatty Acids ◽

Lipid Accumulation ◽

Volatile Fatty Acids ◽

Batch Cultivation ◽

Metschnikowia Pulcherrima ◽

Repeated Batch

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Lipid Accumulation and Chronic Kidney Disease

Nutrients ◽

10.3390/nu11040722 ◽

2019 ◽

Vol 11 (4) ◽

pp. 722 ◽

Cited By ~ 34

Author(s):

Zhibo Gai ◽

Tianqi Wang ◽

Michele Visentin ◽

Gerd Kullak-Ublick ◽

Xianjun Fu ◽

...

Keyword(s):

Chronic Kidney Disease ◽

Fatty Acids ◽

Fatty Acid ◽

Kidney Disease ◽

Lipid Accumulation ◽

Scavenger Receptor ◽

Fatty Acid Uptake ◽

Lipid Lowering ◽

Fatty Acid Transport ◽

Acid Uptake

Obesity and hyperlipidemia are the most prevalent independent risk factors of chronic kidney disease (CKD), suggesting that lipid accumulation in the renal parenchyma is detrimental to renal function. Non-esterified fatty acids (also known as free fatty acids, FFA) are especially harmful to the kidneys. A concerted, increased FFA uptake due to high fat diets, overexpression of fatty acid uptake systems such as the CD36 scavenger receptor and the fatty acid transport proteins, and a reduced β-oxidation rate underlie the intracellular lipid accumulation in non-adipose tissues. FFAs in excess can damage podocytes, proximal tubular epithelial cells and the tubulointerstitial tissue through various mechanisms, in particular by boosting the production of reactive oxygen species (ROS) and lipid peroxidation, promoting mitochondrial damage and tissue inflammation, which result in glomerular and tubular lesions. Not all lipids are bad for the kidneys: polyunsaturated fatty acids (PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) seem to help lag the progression of chronic kidney disease (CKD). Lifestyle interventions, especially dietary adjustments, and lipid-lowering drugs can contribute to improve the clinical outcome of patients with CKD.

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Abstract 037: Role of Pro-opiomelanocortin (POMC) Specific PTP1B in Differential Regulation of Blood Pressure, Liver Lipid Accumulation and Glucose Tolerance in Response to a High Fat Diet

Hypertension ◽

10.1161/hyp.68.suppl_1.037 ◽

2016 ◽

Vol 68 (suppl_1) ◽

Author(s):

Nicola Aberdein ◽

Jussara M do Carmo ◽

Zhen Wang ◽

Taolin Fang ◽

Cecilia P de Lara ◽

...

Keyword(s):

Blood Pressure ◽

Glucose Tolerance ◽

Fat Mass ◽

Lipid Accumulation ◽

High Fat Diet ◽

Acute Stress ◽

Liver Lipid ◽

Liver Weight ◽

Metabolic Effects ◽

High Fat

Obese subjects are often resistant to leptin’s metabolic effects although blood pressure (BP) and sympathetic nervous system responses appear to be preserved. Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of leptin signaling, may play a role in promoting this selective leptin resistance and causing metabolic dysfunction in obesity. Our previous studies suggest that the chronic BP responses to leptin are mediated via activation of pro-opiomelanocortin (POMC) neurons. The goal of this study was to determine if PTP1B in POMC neurons differentially controls metabolic functions and BP in mice fed a high fat diet (HFD). Male mice with POMC specific PTP1B deletion (POMC/PTP1B -/- ) and littermate controls (PTP1B flox/flox ) were fed a HFD from 6 to 22 wks of age. Baseline BP after 16 weeks of a HFD (95±2 vs. 95±3 mmHg) and BP responses to acute stress (Δ32±0 vs. Δ32±6 mmHg), measured by telemetry, were not different in POMC/PTP1B -/- compared to control mice, respectively. Heart rate (HR) was not different in POMC/PTP1B -/- and control mice during acute stress (699±4 vs. 697±15 bpm, respectively). Total body weight (TBW) and fat mass were reduced at 20 weeks of age in POMC/PTP1B -/- compared to controls (36.7±0.1 vs. 42.0±1 g TBW and 12.7±0.4 vs. 16.1±1.0 g fat mass, respectively). Liver weight of POMC/PTP1B -/- mice was less than in controls, and this was evident even when liver weight was normalized as % of TBW (4.5±0.2 vs. 5.0±0.2 %). POMC/PTP1B -/- males had reduced liver lipid accumulation compared to controls as measured by EchoMRI (0.08±0.03 vs. 0.15±0.03 g/g liver weight). Glucose tolerance was also improved by 46% in POMC/PTP1B -/- compared to controls as measured by AUC, 25856±1683 vs. 47267±5616 mg/dLx120min, respectively. These findings indicate that PTP1B signaling in POMC neurons plays a crucial role in regulating liver lipid accumulation and glucose tolerance but does not appear to mediate changes in BP or BP responses to acute stress in mice fed a high HFD (supported by NHLBI-PO1HL51971 and NIGMS P20GM104357)

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