Assessment of virgin coconut oil in a balanced diet on indicators of cardiovascular health in non-obese volunteers: A human metabolic study.

Background And Aims: Consumption of coconut oil is implicated in cardiovascular disease risk. On the contrary, virgin coconut oil (VCO) is believed to offer better health benefits, however, the evidence to support such claims is lacking, particularly in humans. Therefore, this study aimed at assessing the impact of VCO in a balanced diet on HDL-C and some of the anthropometric and biochemical parameters associated with human cardiovascular health before and after the feeding experiment.

Stearoyl-CoA desaturase 1: A potential target for non-alcoholic fatty liver disease?-perspective on emerging experimental evidence.

Non-alcoholic fatty liver disease (NAFLD) is a progressive disease and one of the leading causes of death. An unnamed disease has become a global epidemic disease of public health concern. This spectrum of diseases manifests itself with initial accumulation of excessive triglycerides (due to lipogenesis) in the hepatocytes, leading to simple steatosis.

Pharmaconutrition strategy to resolve SARS-CoV-2-induced inflammatory cytokine storm in non-alcoholic fatty liver disease: Omega-3 long-chain polyunsaturated fatty acids.

Inflammation is one of the primary factors associated with the causation and/or progression of several lifestyle disorders, including obesity, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). NAFLD is a spectrum of disorders, and starts with simple steatosis, progresses to non-alcoholic steatohepatitis, and then advances to fibrosis, cirrhosis and finally, hepatocellular carcinoma, due to perpetual cycles of insults caused by inflammation and other cellular stress. Emerging evidence has documented that patients with NAFLD have severe coronavirus disease 2019 (COVID-19), and patients with COVID-19 have a higher liver injury and mortality.

Carrot Juice Consumption Reduces High Fructose-Induced Adiposity in Rats and Body Weight and BMI in Type 2 Diabetic Subjects.

Nutritional intervention is a key strategy in the control and management of non-communicable diseases. Here, initially, we evaluated the effects of carrot juice (CJ) on some of the physical and biochemical parameters in rats fed with high-fructose diet, then in type 2 diabetic subjects. For the animal study, weanling male Wistar rats were given control (n = 6) or high fructose (HFr; n = 24) diet for 8 weeks.

Consumption of vitamin A-deficient diet elevates endoplasmic reticulum stress marker and suppresses high fructose-induced orexigenic gene expression in the brain of male Wistar rats.

Objective: Here, we assessed the impact of vitamin A deficiency (both alone and in combination with fructose) on the retinol status, phospholipids fatty acid composition and pathways associated with the endoplasmic reticulum (ER) stress and energy homeostasis of the brain. For this purpose, weanling male Wistar rats were divided into four groups consisting of 8 rats each, except 16 for the second group and they received one of the following diets; control, vitamin A-deficient (VAD), high fructose (HFr) and HFr with VAD for 16 weeks, except half of the VAD diet-fed rats, were shifted to HFr diet, after 8 weeks period.

Results: The retinol content of the whole brain remained comparable across the groups, despite a significant reduction in the plasma at the end of VAD diet feeding.

High-Fat Diet Elevates Liver Docosahexaenoic Acid Possibly through Over-Expression of Very Long-Chain Fatty Acid Elongase 2 in C57BL/6J Mice.

The liver is the main site of lipid metabolism and vitamin A storage. Dietary factors are known to affect liver function, thereby leading to metabolic abnormalities. Here, we assessed the impact of long-term feeding of a high-fat diet on hepatic vitamin A status and lipid metabolism.

Vitamin A Improves Hyperglycemia and Glucose-Intolerance through Regulation of Intracellular Signaling Pathways and Glycogen Synthesis in WNIN/GR-Ob Obese Rat Model.

Vitamin A and its metabolites modulate insulin resistance and regulate stearoyl-CoA desaturase 1 (SCD1), which are also known to affect insulin resistance. Here, we tested, whether vitamin A-mediated changes in insulin resistance markers are associated with SCD1 regulation or not. For this purpose, 30-week old male lean and glucose-intolerant obese rats of WNIN/GR-Ob strain were given either a stock or vitamin A-enriched diet, i.

Transcriptome profiling of visceral adipose tissue in a novel obese rat model, WNIN/Ob & its comparison with other animal models.

Background & Objectives: Adipose tissue dysfunction in obesity is linked to the development of type 2 diabetes and cardiovascular diseases. We studied the differential gene expression in retroperitoneal adipose tissue of a novel obese rat model, WNIN/Ob, to understand the possible underlying transcriptional changes involved in the development of obesity and associatedcomorbidities in this model.

Methods: Four month old, male WNIN/Ob lean and obese rats were taken, blood was collected and tissues were dissected.

Chronic vitamin A-enriched diet feeding regulates hypercholesterolaemia through transcriptional regulation of reverse cholesterol transport pathway genes in obese rat model of WNIN/GR-Ob strain.

Background & Objectives: Hepatic scavenger receptor class B1 (SR-B1), a high-density lipoprotein (HDL) receptor, is involved in the selective uptake of HDL-associated esterified cholesterol (EC), thereby regulates cholesterol homoeostasis and improves reverse cholesterol transport. Previously, we reported in euglycaemic obese rats (WNIN/Ob strain) that feeding of vitamin A-enriched diet normalized hypercholesterolaemia, possibly through hepatic SR-B1-mediated pathway. This study was aimed to test whether it would be possible to normalize hypercholesterolaemia in glucose-intolerant obese rat model (WNIN/GR/Ob) through similar mechanism by feeding identical vitamin A-enriched diet.

Carrot Juice Administration Decreases Liver Stearoyl-CoA Desaturase 1 and Improves Docosahexaenoic Acid Levels, but Not Steatosis in High Fructose Diet-Fed Weanling Wistar Rats.

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent liver diseases associated with an altered lifestyle, besides genetic factors. The control and management of NAFLD mostly depend on lifestyle modifications, due to the lack of a specific therapeutic approach. In this context, we assessed the effect of carrot juice on the development of high fructose-induced hepatic steatosis.

Carrot juice ingestion attenuates high fructose-induced circulatory pro-inflammatory mediators in weanling Wistar rats.

Background: Adipose tissue, an endocrine organ, plays a vital role not only in energy homeostasis, but also in the development and/or progression of various metabolic diseases, such as insulin resistance, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD), via several factors and mechanisms, including inflammation. This study tested, whether carrot juice administration affected the adipose tissue development and its inflammatory status in a high fructose diet-induced rat model. For this purpose, male weanling Wistar rats were divided into four groups and fed either control or high fructose diet of AIN-93G composition with or without carrot juice ingestion for an 8 week period.

Vitamin A deficiency suppresses high fructose-induced triglyceride synthesis and elevates resolvin D1 levels.

Background/aims: Vitamin A and its metabolites are known to regulate lipid metabolism. However so far, no study has assessed, whether vitamin A deficiency per se aggravates or attenuates the development of non-alcoholic fatty liver disease (NAFLD). Therefore, here, we tested the impact of vitamin A deficiency on the development of NAFLD.

Vitamin A as a key regulator of obesity & its associated disorders: Evidences from an obese rat model.

During the last century, vitamin A has evolved from its classical role as a fat-soluble vitamin and attained the status of para-/autocrine hormone. Besides its well-established role in embryogenesis, growth and development, reproduction and vision, vitamin A has also been implicated in several other physiological processes. Emerging experimental evidences emphasize adipose tissue as an active endocrine organ with great propensity to continuous growth (throughout life).

Chronic vitamin A-enriched diet feeding induces body weight gain and adiposity in lean and glucose-intolerant obese rats of WNIN/GR-Ob strain.

What is the central question of this study? Previously, we reported that chronic feeding of a vitamin A-enriched diet to euglycaemic obese rats (WNIN/Ob) ameliorated obesity. Does this diet exert similar effects even with a different genetic background, i.e.

Mitochondriogenesis and apoptosis: possible cause of vitamin A-mediated adipose loss in WNIN/Ob-obese rats.

Background: Previously, we reported that vitamin A-enriched diet (129 mg/kg diet) intake reduces the adiposity development in obese rats of WNIN/Ob strain. Here, we hypothesize that dose lesser than 129 mg of vitamin A/kg diet would also be effective in ameliorating the development of obesity in these rats.

Methods: Five-month-old male lean and obese rats designated as A & B were divided into four subgroups (I, II, III and IV) consisting of 8 rats from each phenotype and received diets containing 2.

Vitamin A-enriched diet modulates reverse cholesterol transport in hypercholesterolemic obese rats of the WNIN/Ob strain.

Aim: Vitamin A plays a major role in lipid metabolism. Previously, we reported that chronic vitamin A feeding (129 mg/kg) for two months normalized the abnormally high plasma HDL-cholesterol (HDL-C) levels in hypercholesterolemic obese rats by upregulating the hepatic scavenger receptor class B type 1 (SR-BI) expression. In this report, we hypothesize that the administration of a dose less than 129 mg of vitamin A/kg would also be effective in lowering the plasma HDL-C levels in these rats.

Carbenoxolone treatment ameliorated metabolic syndrome in WNIN/Ob obese rats, but induced severe fat loss and glucose intolerance in lean rats.

Background: 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) regulates local glucocorticoid action in tissues by catalysing conversion of inactive glucocorticoids to active glucocorticoids. 11β-HSD1 inhibition ameliorates obesity and associated co-morbidities. Here, we tested the effect of 11β-HSD inhibitor, carbenoxolone (CBX) on obesity and associated comorbidities in obese rats of WNIN/Ob strain, a new animal model for genetic obesity.

Vitamin A supplementation ameliorates obesity-associated retinal degeneration in WNIN/Ob rats.

Objective: Obesity is associated with various health afflictions, including ocular complications such as diabetic retinopathy, high intraocular pressure, cataracts, and macular degeneration. We previously reported progressive retinal degeneration after the onset of obesity in the spontaneously obese rat (WNIN/Ob) model. In the present study, we investigated vitamin A supplementation to ameliorate obesity-associated retinal degeneration in the WNIN/Ob rat.

Chronic consumption of trans-fat-rich diet increases hepatic cholesterol levels and impairs muscle insulin sensitivity without leading to hepatic steatosis and hypertriglyceridemia in female Fischer rats.

Background: The impact of industrial trans fatty acids (TFAs) on lipid metabolism and health remains elusive.

Methods: We compared the effect of long-term (52 weeks) ingestion of 10% partially hydrogenated vegetable oil, providing 4.2% of total energy from TFAs, on hepatic lipid metabolism and muscle insulin sensitivity in weanling female Fischer rats with that of palmolein (monounsaturated fatty acid, MUFA), sunflower (n-6 polyunsaturated fatty acid, PUFA), and a blend of sunflower and fish oil (n-3 PUFA).

Vitamin A decreases pre-receptor amplification of glucocorticoids in obesity: study on the effect of vitamin A on 11beta-hydroxysteroid dehydrogenase type 1 activity in liver and visceral fat of WNIN/Ob obese rats.

Background: 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of inactive glucocorticoids to active glucocorticoids and its inhibition ameliorates obesity and metabolic syndrome. So far, no studies have reported the effect of dietary vitamin A on 11β-HSD1 activity in visceral fat and liver under normal and obese conditions. Here, we studied the effect of chronic feeding of vitamin A-enriched diet (129 mg/kg diet) on 11β-HSD1 activity in liver and visceral fat of WNIN/Ob lean and obese rats.

A novel genetically-obese rat model with elevated 11 beta-hydroxysteroid dehydrogenase type 1 activity in subcutaneous adipose tissue.

11 β-hydroxysteroid dehydrogenase type 1 (11 β-HSD1) catalyzes the conversion of inactive glucocorticoids to active glucocorticoids and plays an important role in the development of obesity and metabolic syndrome. 11 β-HSD1 activity is lower in liver and higher in omental adipose tissue of obese rodent models like obese zucker rats, Ob/Ob and db/db mice. Here, we report the 11 β-HSD1 activity in liver and adipose tissue of lean and obese rats of WNIN/Ob strain, a new genetic rat model of obesity.

Dietary fatty acid composition alters 11β-hydroxysteroid dehydrogenase type 1 gene expression in rat retroperitoneal white adipose tissue.

The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) amplifies intracellular glucocorticoid action by converting inactive glucocorticoids to their active forms in vivo. Adipose-specific overexpression of 11β-HSD1 induces metabolic syndrome in mice, whereas 11β-HSD1 null mice are resistant to it. Dietary trans and saturated fatty acids (TFAs and SFAs) are involved in the development of metabolic syndrome, whereas polyunsaturated fatty acids (PUFA) offer protection against this.

Fatty acid desaturation index correlates with body mass and adiposity indices of obesity in Wistar NIN obese mutant rat strains WNIN/Ob and WNIN/GR-Ob.

Background: Microsomal stearoyl-CoA desaturase1 (SCD1) is the rate limiting enzyme involved in the biosynthesis of monounsaturated fatty acids (MUFAs); palmitoleic (16:1) and oleic (18:1) acid from their respective substrates palmitic (16:0) and stearic (18:0) acids. The ratio of 18:1 to 18:0 has been implicated in the regulation membrane fluidity and function. SCD1 is abundantly expressed in obese humans as well as rodent models.

Impact of feeding polyunsaturated fatty acids on cholesterol metabolism of dyslipidemic obese rats of WNIN/GR-Ob strain.

Dietary fatty acids are known to play an important role in the development as well as prevention of dyslipidemia. In this study, we evaluated the impact of feeding polyunsaturated fatty acids (PUFAs) for a period of 4 months on various aspects of cholesterol metabolism in genetically obese mutant rats of WNIN/GR-Ob strain. Based on their phenotype, lean and obese rats were divided into two groups, A and B respectively, and further subdivided depending on the type of dietary fat.

Impact of vitamin A on high-density lipoprotein-cholesterol and scavenger receptor class BI in the obese rat.

Objective: Scavenger receptor class BI (SR-BI), authentic high-density lipoprotein (HDL) receptors expressed in liver, are known to play an important role in HDL-cholesterol (C) metabolism and reverse cholesterol transport. Interestingly, obese rats of WNIN/Ob strain have abnormally elevated levels of serum HDL-C compared with their lean counterparts. Based on the well-established role of SR-B1 in HDL-C metabolism, it was hypothesized that these obese rats may have an underexpression of hepatic SR-B1 receptors.