Partial Replacement of High-Fat Diet with Beef Tallow Attenuates Dyslipidemia and Endoplasmic Reticulum Stress in db/db Mice.

High-fat diet (HFD) consumption is closely associated with an increased risk of metabolic syndromes (MetS), such as obesity, type 2 diabetes, and cardiovascular diseases (CVDs). Therefore, the consumption of alternative and functional fatty acids to replace saturated fatty acids and/or trans-fatty acids with polyunsaturated fatty acids has become an important dietary strategy for the prevention of MetS. Consumption of omega-3 fatty acids (n-3) reduces various physiological complications, including CVDs, nonalcoholic fatty liver disease, and insulin resistance, related to inflammatory responses. In this study, we investigated the partial replacement effects of HFD with beef tallow (BT) on dyslipidemia and endoplasmic reticulum (ER) stress in male db/db mice. The animals were grouped to one of four dietary intervention groups (n = 16 per group): (1) normal diet, (2) HFD, (3) HFD partially replaced with regular beef tallow (HFD+BT1), or (4) HFD partially replaced with beef tallow containing a relatively reduced omega-6 fatty acid (n-6)/n-3 ratio (HFD+BT2) than HFD+BT1. After 6 weeks of dietary intervention, 1 mg/kg of phosphate-buffered saline or tunicamycin (TM) was injected intraperitoneally. HFD+BT2 significantly suppressed the serum total cholesterol and non-high-density lipoprotein cholesterol levels more than HFD and HFD+BT1, and triglyceride levels in the epididymal adipose tissue (EAT) were remarkably decreased. Mice that received HFD+BT2 had elevated protein expressions of phospho-AMP-activated protein kinase (p-AMPK). Moreover, HFD+BT2 effectively inhibited ER stress in the liver and EAT. Consistent with our hypothesis, HFD+BT2 remarkably alleviated dyslipidemia and TM-inducible ER stress, while activating p-AMPK.

Gryllus bimaculatus De Geer hydrolysates alleviate lipid accumulation, inflammation, and endoplasmic reticulum stress in palmitic acid-treated human hepatoma G2 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Nonalcoholic fatty liver disease (NAFLD) is one of the most common hepatic diseases closely intertwined with saturated fatty acids intake. Therefore, various studies are being conducted to find natural substances to prevent either the onset or progression of NAFLD. According to traditional medicinal literature, it has been reported that Gryllus bimaculatus De Geer (GB) has systemic detoxifying activity; however, the preventive effects of GB on NAFLD have not been elucidated to date. AIM OF STUDY: To evaluate the potential of GB as a material for the mitigation of NAFLD, we investigated the effects of GB hydrolysates on the hepatic lipid accumulation, inflammation, and endoplasmic reticulum (ER) stress in human hepatoma G2 (Hep G2) cells treated with palmitic acid (PA). METHODS: Steamed and dried GB was defatted, pulverized, and then lyophilized following hydrolyzation using Neutrase® (GB-N) or Flavourzyme® (GB-F). Hep G2 cells were incubated with GB-N or GB-F at various concentrations (0, 0.25, 0.5, and 1 mg/mL) for 24 h, and then PA was treated for another 24 h. RESULTS: The GB-N and GB-F significantly prevented the PA-induced intracellular lipid accumulation in the human liver cells (p < 0.05). Moreover, the GB-N and GB-F increased the hepatic cellular viability against the PA-treatment (p < 0.05). In addition, the GB-N and GB-F significantly ameliorated the PA-inducible proinflammatory cytokines mRNA expression, such as tumor necrosis factor-α and interleukin-1ß, compared to the PA-treated hepatic cells (p < 0.05). Furthermore, the GB-N and GB-F inhibited the PA-inducible lipogenic mRNA expression, such as fatty acid synthase, sterol regulatory element-binding protein 1c, and peroxisome proliferator-activated receptor-γ (p < 0.05). Moreover, the GB-N and GB-F alleviated the ER stress-related mRNA expression, such as glucose regulatory protein 78 and X-box binding protein increased in PA-treated cells (p < 0.05). CONCLUSIONS: These results indicate that GB-N and GB-F could be used as materials to prevent the NAFLD onset or progression with alleviating hepatic lipid accumulation, inflammation, and ER stress.

Partial Replacement of Dietary Fat with Krill Oil or Coconut Oil Alleviates Dyslipidemia by Partly Modulating Lipid Metabolism in Lipopolysaccharide-Injected Rats on a High-Fat Diet.

This study investigated the effects of partial replacement of dietary fat with krill oil (KO) or coconut oil (CO) on dyslipidemia and lipid metabolism in rats fed with a high-fat diet (HFD). Sprague Dawley rats were divided into three groups as follows: HFD, HFD + KO, and HFD + CO. The rats were fed each diet for 10 weeks and then intraperitoneally injected with phosphate-buffered saline (PBS) or lipopolysaccharide (LPS) (1 mg/kg). The KO- and CO-fed rats exhibited lower levels of serum lipids and aspartate aminotransferases than those of the HFD-fed rats. Rats fed with HFD + KO displayed significantly lower hepatic histological scores and hepatic triglyceride (TG) content than rats fed with HFD. The KO supplementation also downregulated the adipogenic gene expression in the liver. When treated with LPS, the HFD + KO and HFD + CO groups reduced the adipocyte size in the epididymal white adipose tissues (EAT) relative to the HFD group. These results suggest that KO and CO could improve lipid metabolism dysfunction.

Partial Replacement of Dietary Fat with Polyunsaturated Fatty Acids Attenuates the Lipopolysaccharide-Induced Hepatic Inflammation in Sprague-Dawley Rats Fed a High-Fat Diet.

In this study, we investigated whether the partial replacement of dietary fat with polyunsaturated fatty acids (PUFAs) ameliorated the lipopolysaccharide (LPS)-induced hepatic inflammation in rats fed a high-fat diet. Male Sprague-Dawley rats were divided into three groups and provided each of the following diets: (1) high-fat diet (HFD), (2) HFD with perilla oil (PO), and (3) HFD with corn oil (CO). After 12 weeks of dietary intervention, the rats were intraperitoneally injected with LPS (5 mg/kg) from Escherichia coli O55:B5 or phosphate-buffered saline (PBS). Following LPS stimulation, serum insulin levels were increased, while PO and CO lowered the serum levels of glucose and insulin. In the liver, LPS increased the triglyceride levels, while PO and CO alleviated the LPS-induced hepatic triglyceride accumulation. In the LPS injected rats, the mRNA expression of genes related to inflammation and endoplasmic reticulum (ER) stress was attenuated by PO and CO in the liver. Furthermore, hepatic levels of proteins involved in the nuclear factor kappa-light-chain-enhancer of activated B cells/mitogen-activated protein kinase pathways, antioxidant response, and ER stress were lowered by PO- and CO-replacement. Therefore, the partial replacement of dietary fat with PUFAs alleviates LPS-induced hepatic inflammation during HFD consumption, which may decrease metabolic abnormalities.

Mulberry (Morus alba L.) Fruit Extract Ameliorates Inflammation via Regulating MicroRNA-21/132/143 Expression and Increases the Skeletal Muscle Mitochondrial Content and AMPK/SIRT Activities.

The Mulberry (Morus alba L.) fruit is a rich source of polyphenolic compounds; most of these are anthocyanins. Obesity is intimately related to low-grade inflammation, with increased pro-inflammatory cytokine secretion and macrophage infiltration in white adipose tissue (WAT). This study investigated whether mulberry fruit extract (ME) has beneficial effects on obesity-induced inflammation and skeletal muscle mitochondrial dysfunction. Sprague-Dawley rats were divided into four groups and fed either a low-fat diet (LFD), high-fat diet (HFD), HFD + 5 g/kg of ME (ME-L), or HFD + 10 g/kg of ME (ME-H) for 14 weeks. ME alleviated dyslipidemia and lipid accumulation, as well as pro-inflammatory cytokine production such as tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and monocyte chemoattractant protein 1 (MCP1) in the WAT. ME mitigated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) phosphorylation and macrophage infiltration in WAT. Notably, microRNA (miR)-21, miR-132, and miR-43 expressions were downregulated in the WAT of the ME groups compared to the HFD group. Moreover, ME increased the mitochondrial size and mitochondrial DNA (mtDNA) content, as well as key genes' expression related to mitochondrial function, including sirtuin (SIRT)1, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), carnitine palmitoyltransferase 1ß (CPT-1ß), and uncoupling protein 3 (UCP3), and adenosine monophosphate-activated protein kinase (AMPK)/SIRT activities in skeletal muscle. These results suggested that ME might alleviate obesity-induced inflammation and mitochondrial dysfunction by regulating miR-21, miR-132, and miR-43 expression in WAT, and by activating the PGC-1α/SIRT1 pathway in muscle.

Effect of Soybean and Soybean Koji on Obesity and Dyslipidemia in Rats Fed a High-Fat Diet: A Comparative Study.

Soybean koji refers to steamed soybeans inoculated with microbial species. Soybean fermentation improves the health benefits of soybeans. Obesity is a serious health concern owing to its increasing incidence rate and high association with other metabolic diseases. Therefore, we investigated the effects of soybean and soybean koji on high-fat diet-induced obesity in rats. Five-week-old male Sprague-Dawley rats were randomly divided into four groups (n = 8/group) as follows: (1) regular diet (RD), (2) high-fat diet (HFD), (3) HFD + steamed soybean (HFD+SS), and (4) HFD + soybean koji (HFD+SK). SK contained more free amino acids and unsaturated fatty acids than SS. In a rat model of obesity, SK consumption significantly alleviated the increase in weight of white adipose tissue and mRNA expression of lipogenic genes, whereas SS consumption did not. Both SS and SK reduced serum triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels, and increased high-density lipoprotein cholesterol levels. SS and SK also inhibited lipid accumulation in the liver and white adipose tissue and reduced adipocyte size. Although both SS and SK could alleviate HFD-induced dyslipidemia, SK has better anti-obesity effects than SS by regulating lipogenesis. Overall, SK is an excellent functional food that may prevent obesity.

Physicochemical characteristics of Ethiopian Coffea arabica cv. Heirloom coffee extracts with various roasting conditions.

This study aimed to investigate the physicochemical characteristics of Ethiopian Coffea arabica cv. Heirloom coffee extracts with various roasting conditions. Green coffee beans were roasted at four different conditions (Light-medium, Medium, Moderately dark, and Very dark) and used to extract espresso and drip coffee. Moisture content in coffee beans was decreased as the roasting degree increased. The contents of crude fat and ash were lower in the Light-medium roasted coffee beans than in green coffee beans but increased as the roasting degree increased. The values of lightness (L*), redness (a*), yellowness (b*), and browning index of coffee extracts were decreased as the roasting degree increased. Total dissolved solids in espresso coffee were increased with increasing roasting degree but decreased in drip coffee. In both the extracts, the contents of reducing sugar, titratable acidity, organic acids, and chlorogenic acid were decreased, but that of caffeine was increased with the roasting degree increased. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-020-00865-w.

Anti-Inflammatory Effects of High Hydrostatic Pressure Extract of Mulberry (Morus alba) Fruit on LPS-Stimulated RAW264.7 Cells.

Mulberry fruit (Morus alba L.) contains abundant bioactive compounds, including anthocyanins and flavonols, and has been reported to possess potent beneficial properties including anticancer, antidiabetic, and anti-oxidant effects. High hydrostatic pressure (HHP) processing, a nonthermal food processing technology, is suitable for the extraction of bioactive compounds from plants. Nevertheless, the anti-inflammatory effects of HHP extract of mulberry fruit (HM) in RAW264.7 cells remain unclear. The present study aimed to investigate the anti-inflammatory effects of HM on lipopolysaccharide (LPS)-induced inflammation in vitro. RAW264.7 cells were treated with various concentrations (0.1-1 µg/mL) of HM in the presence or absence of LPS. HM inhibited the inflammatory mediator, nitric oxide (NO) release, and mRNA expression of nitric oxide synthase 2 (NOS2) in LPS-induced RAW264.7 cells. In addition, HM suppressed both mRNA and protein expressions of prostaglandin-endoperoxide synthase 2 (PTGS2). Moreover, it reduced the LPS-induced secretion of proinflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α. These results revealed that HM exerts anti-inflammatory effects by inhibiting several mediators and cytokines involved in the inflammatory process.

Tartary Buckwheat Extract Attenuated the Obesity-Induced Inflammation and Increased Muscle PGC-1a/SIRT1 Expression in High Fat Diet-Induced Obese Rats.

Obesity is intimately related to a chronic inflammatory state, with augmentation of macrophage infiltration and pro-inflammatory cytokine secretion in white adipose tissue (WAT) and mitochondrial dysfunction in skeletal muscle. The specific aim of this study is to evaluate effects of tartary buckwheat extract (TB) on obesity-induced adipose tissue inflammation and muscle peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α/sirtulin 1 (SIRT1) pathway in rats fed a high-fat diet. Sprague-Dawley rats were divided into four groups and fed either a normal diet (NOR), 45% high-fat diet (HF), HF + low dose of TB (TB-L; 5 g/kg diet), or HF + high dose of TB (TB-H; 10 g/kg diet) for 13 weeks. TB significantly reduced adipose tissue mass with decreased adipogenic gene expression of PPAR-γ and aP2. Serum nitric oxide levels and adipose tissue macrophage M1 polarization gene markers, such as iNOS, CD11c, and Arg1, and pro-inflammatory gene expression, including TNF-α, IL-6, and MCP-1, were remarkably downregulated in the TB-L and TB-H groups. Moreover, TB supplementation increased gene expression of PGC-1α and SIRT1, involved in muscle biogenesis and function. These results suggested that TB might attenuate obesity-induced inflammation and mitochondrial dysfunction by modulating adipose tissue inflammation and the muscle PGC-1α/SIRT1 pathway.

Ginger Extract Ameliorates Obesity and Inflammation via Regulating MicroRNA-21/132 Expression and AMPK Activation in White Adipose Tissue.

Ginger is a plant whose rhizome is used as a spice or folk medicine. We aimed to investigate the effect of ginger root extract on obesity and inflammation in rats fed a high-fat diet. Sprague-Dawley rats were divided into three groups and fed either a 45% high-fat diet (HF), HF + hot-water extract of ginger (WEG; 8 g/kg diet), or HF + high-hydrostatic pressure extract of ginger (HPG; 8 g/kg diet) for 10 weeks. The HPG group had lower body weight and white adipose tissue (WAT) mass compared to the HF group. Serum and hepatic lipid levels of HPG group were lower, while fecal lipid excretion of the HPG group was higher than that of the HF group. In the WAT of the WEG and HPG groups, mRNA levels of adipogenic genes were lower than those of the HF group. Moreover, HPG group had lower mRNA levels of pro-inflammatory cytokines than did the HF group. MicroRNA (miR)-21 expression was down-regulated by both WEG and HPG. Additionally, miR-132 expression was down-regulated by HPG. The adenosine monophosphate-activated protein kinase (AMPK) activity of HPG group was greater than that of the HF group. HPG may have beneficial effects on obesity and inflammation, partially mediated by regulation of miR-21/132 expression and AMPK activation in WAT.

Echinacea purpurea Protects Against Restraint Stress-Induced Immunosuppression in BALB/c Mice.

Echinacea purpurea has been widely used for the prevention and treatment of upper respiratory tract infections and the common cold. The restraint stress has been reported to suppress a broad spectrum of immune functions. The aim of this study was to investigate the protective effects of the pressed juice of E. purpurea (L.) Moench (EFLA®894; Echinacea) against restraint stress-induced immunosuppression in BALB/c mice. Echinacea significantly normalized the restraint stress-induced reduction in splenocyte proliferation and splenic natural killer (NK) cell activity (P < .05). Echinacea treatment significantly increased the percentages of CD4+ and CD8+ T lymphocytes in the blood (P < .05). In addition, Echinacea restored serum cytokine levels, including interleukin-6 (IL-6), interleukin-10 (IL-10), and interleukin-17 (IL-17), as well as the mRNA expressions of these cytokines in spleen (P < .05). Our findings suggest that Echinacea might have beneficial effects on restraint stress-induced immunosuppression by increasing splenocyte proliferation and NK cell activity, while modulating T lymphocyte subsets and cytokine levels in the blood.

Lipolytic efficacy of alginate double-layer nanoemulsion containing oleoresin capsicum in differentiated 3T3-L1 adipocytes.

Background: Oleoresin capsicum (OC) is an organic extract from fruits of the genus Capsicum, and has been reported to have an anti-obesity effect. Objective: This study comparatively investigated lipolytic effects of single-layer nanoemulsion (SN) and alginate double-layer nanoemulsion (AN) containing OC in 3T3-L1 adipocytes. Methods: SN and AN were compared by analyzing the intracellular lipid accumulation, triglyceride (TG) content, release of free fatty acids (FFAs) and glycerol, and mRNA expression of genes related to adipogenesis and lipolysis were analyzed in fully differentiated 3T3-L1 adipocytes. Results: Compared with SN, AN exhibited higher efficiency in inhibiting the intracellular lipid accumulation and TG content, and enhanced the release of FFAs and glycerol into the medium. In AN-treated cells, mRNA levels of peroxisome proliferator-activated receptor-γ and the fatty acid-binding protein adipocyte protein-2, which are involved in adipogenesis, were down-regulated, whereas those of genes related to lipolysis, including hormone-sensitive lipase and carnitine palmitoyl transferase-1α, were up-regulated compared with SN-treated cells. Conclusion: The lipolytic effect of AN was greater than that of SN; this was partly associated with the increased TG hydrolysis via induction of lipolytic gene expression and suppression of adipogenic gene expression in 3T3-L1 adipocytes.​​​​.

High Hydrostatic Pressure Extract of Ginger Exerts Antistress Effects in Immobilization-Stressed Rats.

Stress contributes to physiological changes such as weight loss and hormonal imbalances. The aim of the present study was to investigate antistress effects of high hydrostatic pressure extract of ginger (HPG) in immobilization-stressed rats. Male Sprague-Dawley rats (n = 24) were divided into three groups as follows: control (C), immobilization stress (2 h daily, for 2 weeks) (S), and immobilization stress (2 h daily, for 2 weeks) plus oral administration of HPG (150 mg/kg body weight/day) (S+G). Immobilization stress reduced the body weight gain and thymus weight by 50.2% and 31.3%, respectively, compared to the control group. The levels of serum aspartate transaminase, alanine transaminase, and corticosterone were significantly higher in the stress group, compared to the control group. Moreover, immobilization stress elevated the mRNA levels of tyrosine hydroxylase (Th), dopamine beta-hydroxylase (Dbh), and cytochrome P450 side-chain cleavage (P450scc), which are related to catecholamine and corticosterone synthesis in the adrenal gland. HPG administration also increased the body weight gain and thymus weight by 12.7% and 16.6%, respectively, compared to the stress group. Furthermore, the mRNA levels of Th, Dbh, phenylethanolamine-N-methyltransferase, and P450scc were elevated by the HPG treatment when compared to the stress group. These results suggest that HPG would have antistress effects partially via the reversal of stress-induced physiological changes and suppression of mRNA expression of genes related to corticosterone and catecholamine synthetic enzymes.

The Inhibitory Effect of Tartary Buckwheat Extracts on Adipogenesis and Inflammatory Response.

Tartary buckwheat (Fagopyrum tataricum) has been established globally as a nutritionally important food item, particularly owing to high levels of bioactive compounds such as rutin. This study investigated the effect of tartary buckwheat extracts (TBEs) on adipogenesis and inflammatory response in 3T3-L1 cells. TBEs inhibited lipid accumulation, triglyceride content, and glycerol-3-phosphate dehydrogenase (GPDH) activity during adipocyte differentiation of 3T3 L1 cells. The mRNA levels of genes involved in fatty acid synthesis, such as peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer binding protein-α (CEBP-α), adipocyte protein 2 (aP2), acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and stearoylcoenzyme A desaturase-1 (SCD-1), were suppressed by TBEs. They also reduced the mRNA levels of inflammatory mediators such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein 1 (MCP-1), and inducible nitric oxide synthase (iNOS). In addition, TBEs were decreased nitric oxide (NO) production. These results suggest that TBEs may inhibit adipogenesis and inflammatory response; therefore, they seem to be beneficial as a food ingredient to prevent obesity-associated inflammation.

Effects of epigallocatechin-3-gallate on thermogenesis and mitochondrial biogenesis in brown adipose tissues of diet-induced obese mice.

Background: Epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea and has been considered a natural agent that can help to reduce the risk of obesity. Objective: The aim of this study was to investigate the effects of EGCG on thermogenesis and mitochondrial biogenesis in brown adipose tissue (BAT) of diet-induced obese mice. Methods: Male C57BL/6J mice were provided a high-fat diet for 8 weeks to induce obesity, following which they were divided into two groups: one on a high-fat control diet and the other on a 0.2% EGCG (w/w)-supplemented high-fat diet for another 8 weeks. Results: The EGCG-supplemented group showed decreased body weight gain, and plasma and liver lipids. EGCG-fed mice exhibited higher body temperature and mitochondrial DNA (mtDNA) content in BAT. The messenger RNA levels of genes related to thermogenesis and mitochondrial biogenesis in BAT were increased by EGCG. Moreover, adenosine monophosphate-activated protein kinase (AMPK) activity in BAT was stimulated by EGCG. Conclusions: The results suggest that EGCG may have anti-obesity properties through BAT thermogenesis and mitochondria biogenesis, which are partially associated with the regulation of genes related to thermogenesis and mitochondria biogenesis, and the increase in mtDNA replication and AMPK activation in BAT of diet-induced obese mice.

Effect of high hydrostatic pressure extract of fresh ginseng on adipogenesis in 3T3-L1 adipocytes.

BACKGROUND: Red ginseng is produced by steaming and drying fresh ginseng. Through this processing, chemical compounds are modified, and then biological activities are changed. In the food-processing industry, high hydrostatic pressure (HHP) has become an alternative to heat processing to make maximum use of bioactive compounds in food materials. This study comparatively investigated the anti-adipogenic effects of water extract of red ginseng (WRG) and high hydrostatic pressure extract of fresh ginseng (HPG) in 3T3-L1 adipocytes. RESULTS: Both WRG and HPG inhibited the accumulation of intracellular lipids and triglycerides, and the activity of glycerol-3-phosphate dehydrogenase (GPDH), a key enzyme in triglyceride biosynthesis. Intracellular lipid content and GPDH activity were significantly lower in the HPG group compared to the WRG group. In addition, mRNA expression of adipogenic genes, including CEBP-α, SREBP-1c and aP2, were lower in HPG-treated cells compared to WRG-treated cells. HPG significantly increased the activity of AMPK, and WRG did not. CONCLUSION: Results suggested that HPG may have superior beneficial effects on the inhibition of adipogenesis compared with WRG. The anti-adipogenic effects of HPG were partially associated with the inhibition of GPDH activity, suppression of adipogenic gene expression and activation of AMPK in 3T3-L1 adipocytes.

High Hydrostatic Pressure Extract of Red Ginseng Attenuates Inflammation in Rats with High-fat Diet Induced Obesity.

Chronic low-grade inflammation is associated with obesity. This study investigated effect of high hydrostatic pressure extract of red ginseng (HRG) on inflammation in rats with high-fat (HF) diet induced obesity. Male, Sprague-Dawley rats (80~110 g) were randomly divided into two groups, and fed a 45% HF diet (HF) and a 45% HF diet containing 1.5% HRG (HF+HRG) for 14 weeks. At the end of the experiment, the serum leptin level was reduced by the HRG supplementation. The mRNA expression of genes related to adipogenesis including peroxisome proliferator-activated receptor-gamma and adipocyte protein 2 was down-regulated in the white adipose tissue (WAT). The mRNA levels of major inflammatory cytokines such as tumor necrosis factor-α, monocyte chemoattractant protein 1, and interleukin-6 were remarkably down-regulated by the HRG in WAT. These results suggest that HRG might be beneficial in ameliorating the inflammation-associated health complications by suppressing adipogenic and pro-inflammatory gene expression.

Anti-obesity efficacy of nanoemulsion oleoresin capsicum in obese rats fed a high-fat diet.

PURPOSE: This study determined the effects of oleoresin capsicum (OC) and nanoemulsion OC (NOC) on obesity in obese rats fed a high-fat diet. METHODS: THE RATS WERE RANDOMLY SEPARATED INTO THREE GROUPS: a high-fat (HF) diet group, HF + OC diet group, and HF + NOC diet group. All groups were fed the diet and water ad libitum for 14 weeks. RESULTS: NOC reduced the body weight and adipose tissue mass, whereas OC did not. OC and NOC reduced mRNA levels of adipogenic genes, including peroxisome proliferator-activated receptor (PPAR)-γ, sterol regulatory element-binding protein-1c, and fatty acid-binding protein in white adipose tissue. The mRNA levels of genes related to ß-oxidation or thermogenesis including PPAR-α, palmitoyltransferase-1α, and uncoupling protein-2 were increased by the OC and NOC relative to the HF group. Both OC and NOC clearly stimulated AMP-activated protein kinase (AMPK) activity. In particular, PPAR-α, palmitoyltransferase-1α, uncoupling protein-2 expression, and AMPK activity were significantly increased in the NOC group compared to in the OC group. NOC decreased glycerol-3-phosphate dehydrogenase activity whereas OC did not. CONCLUSION: From these results, NOC could be suggested as a potential anti-obesity agent in obese rats fed a HF diet. The effects of the NOC on obesity were associated with changes of multiple gene expression, activation of AMPK, and inhibition of glycerol-3-phosphate dehydrogenase in white adipose tissue.