Fermented Moringa oleifera Decreases Hepatic Adiposity and Ameliorates Glucose Intolerance in High-Fat Diet-Induced Obese Mice.

Metabolic diseases, such as glucose intolerance and nonalcoholic fatty-liver disease (NAFLD), are primary risk factors for life-threatening conditions such as diabetes, heart attack, stroke, and hepatic cancer. Extracts from the tropical tree Moringa oleifera show antidiabetic, antioxidant, anti-inflammatory, and anticancer effects. Fermentation can further improve the safety and nutritional value of certain foods. We investigated the efficacy of fermented M. oleifera extract (FM) against high-fat diet (HFD)-induced glucose intolerance and hepatic lipid accumulation and investigated the underlying mechanisms by analyzing expression of proteins and genes involved in glucose and lipid regulation. C57BL/6 mice were fed with normal chow diet (ND) or HFD supplemented with distilled water (DW, control), nonfermented M. oleifera extract (NFM), or FM for 10 weeks. Although body weights were similar among HFD-fed treatment groups, liver weight was decreased, and glucose tolerance test (GTT) results improved in the FM group compared with DW and NFM groups. Hepatic lipid accumulation was also lower in the FM group, and expressions of genes involved in liver lipid metabolism were upregulated. In addition, HFD-induced endoplasmic reticulum (ER) stress, oxidative stress, and lipotoxicity in quadriceps muscles were decreased by FM. Finally, proinflammatory cytokine mRNA expression was decreased by FM in the liver, epididymal adipose tissue, and quadriceps of HFD-fed mice. FMs may decrease glucose intolerance and NAFLD under HFD-induced obesity by decreasing ER stress, oxidative stress, and inflammation.

Korean solar salts reduce obesity and alter its related markers in diet-induced obese mice.

BACKGROUND/OBJECTIVES: The aim of this experiments was to show anti-obesity effects of Korean solar salt from different salt fields in diet-induced obese mice. SUBJECTS/METHODS: Diet-induced obesity (DIO) was induced by a high-fat diet (HFD; 45% cal from fat) in C57BL/6J mice for eight weeks. The mice were fed with the designated diets (chow diet for Normal, HFD for Control, 0.47%-salt-mixed HFD for purified salt (PS), Guerande solar salt from France (SS-G), solar salt from Y salt field (SS-Y), solar salts from T salt field (SS-T) and S salt field (SS-S)) for another eight weeks. We checked body weight, food efficiency ratio (FER) and tissue weights (liver and epididymal adipose tissue (EAT)), and observed serum concentrations of triacylglycerol (TG), total cholesterol (TC), leptin and insulin. We also evaluated gene expressions of adipogenic / lipogenic mRNAs of C/EBPα, PPARγ and FAS and beta-oxidation-related factors (PPARα and CPT-1) in liver and EAT. The mineral composition of salt samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). RESULTS: SS-T and SS-S significantly reduced body weight gain, FER, and weight of EAT compared to control and other samples (P < 0.05). SS-T and SS-S also significantly decreased serum levels of TG, TC, leptin and insulin (P < 0.05). SS-T and SS-S suppressed expressions of adipogenic / lipogenic mRNAs in liver and EAT, while promoting expression of beta-oxidation-related factors. The lowest sodium concentration was observed in SS-T (30.30 ± 0.59%), and the lowest sodium-to-potassium (Na/K) ratio was found in SS-S (17.81). CONCLUSIONS: Our study shows that well-processed Korean solar salt may have anti-obesity effects in vivo, probably owing to its differences in mineral composition and other components, presumably resulting from the manufacturing processes. Further research is needed into the mechanism and to explore optimal manufacturing processes.

Bamboo Salt Suppresses Colon Carcinogenesis in C57BL/6 Mice with Chemically Induced Colitis.

The aim of our experiment was to evaluate the anticancer effect of bamboo salt (BS) on C57BL/6 mice in an azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon cancer model. BS, solar salt, and purified salt were evaluated for their protective effects during AOM/DSS-induced colon carcinogenesis in C57BL/6 mice. BS, especially after baking for nine separate intervals (BS9x), suppressed colon carcinogenesis in the mice. BS9x decreased colon length shortening, weight-to-length ratios, and tumor counts. Pathological evidence from histological evaluation by hematoxylin and eosin staining also revealed suppression of tumorigenesis. BS9x lowered serum levels of proinflammatory cytokines (TNF-α, IL-6, and IL-1ß) to close to those of the Normal group. Additionally, BS9x suppressed colon mRNA expression of proinflammatory factors and significantly regulated mRNA levels of the apoptosis-related factors, Bax and Bcl-2, and the cell cycle-related genes, p21 and p53. Additionally, immunohistochemistry showed that BS promoted p21 expression in the colon. Taken together, the results indicate that BS exhibited anticancer efficacy by modulating apoptosis- and inflammation-related gene expression during colon carcinogenesis in mice, and repetition in baking cycles of BS enhanced its anticancer functionality.

B-cell-activating factor deficiency attenuates high-fat diet-induced glucose intolerance by potentiating adipose tissue function.

B-cell-activating factor (BAFF) has recently been demonstrated to be expressed in adipocytes and up-regulated by high-fat diet feeding, indicating a possible role in metabolic regulation. Here we show that glucose tolerance was significantly improved in high-fat diet-fed BAFF knockout (BAFF(-/-)) mice. BAFF(-/-) mice revealed higher levels of glucose transporter expression and insulin-stimulated Akt phosphorylation in brown adipose tissue compared to wild type controls. Expression levels of mitochondrial ND5 and genes involved in lipid metabolism were significantly elevated in brown adipose tissue of BAFF(-/-) mice, and this enhancement was found to be mediated by FGF21 and leptin. It was also observed that expression of IL-10 and foxp3 was increased in adipose tissues, as well as PPARγ activity in white adipose tissue. Our findings suggest that suppression of BAFF could have a therapeutic potential for prevention of type 2 diabetes.

BAFF knockout improves systemic inflammation via regulating adipose tissue distribution in high-fat diet-induced obesity.

Obesity is recognized as a chronic low-grade inflammatory state due to adipose tissue expansion being accompanied by an increase in the production of proinflammatory adipokines. Our group is the first to report that B-cell-activating factor (BAFF) is produced from adipocytes and functions as a proinflammatory adipokine. Here, we investigated how loss of BAFF influenced diet-induced obesity in mice by challenging BAFF(-/-) mice with a high-fat diet for 10 weeks. The results demonstrated that weight gain in BAFF(-/-) mice was >30% than in control mice, with a specific increase in the fat mass of the subcutaneous region rather than the abdominal region. Expression of lipogenic genes was examined by quantitative real-time PCR, and increased lipogenesis was observed in the subcutaneous adipose tissue (SAT), whereas lipogenesis in the epididymal adipose tissue (EAT) was reduced. A significant decrease in EAT mass resulted in the downregulation of inflammatory gene expression in EAT, and more importantly, overall levels of inflammatory cytokines in the circulation were reduced in obese BAFF(-/-) mice. We also observed that the macrophages recruited in the enlarged SAT were predominantly M2 macrophages. 3T3-L1 adipocytes were cultured with adipose tissue conditioned media (ATCM), demonstrating that EAT ATCM from BAFF(-/-) mice contains antilipogenic and anti-inflammatory properties. Taken together, BAFF(-/-) improved systemic inflammation by redistributing adipose tissue into subcutaneous regions. Understanding the mechanisms by which BAFF regulates obesity in a tissue-specific manner would provide therapeutic opportunities to target obesity-related chronic diseases.

The Korean Mistletoe (Viscum album coloratum) Extract Has an Antiobesity Effect and Protects against Hepatic Steatosis in Mice with High-Fat Diet-Induced Obesity.

This study investigates the inhibitory effects of Korean mistletoe extract (KME) on adipogenic factors in 3T3-L1 cells and obesity and nonalcoholic fatty liver disease (NAFLD) in mice fed a high-fat diet. Male C57Bl/6 mice fed a high-fat diet were treated with KME (3 g/kg/day) for 15 weeks for the antiobesity and NAFLD experiments. Body weight and daily food intake were measured regularly during the experimental period. The epididymal pad was measured and liver histology was observed. The effects of KME on thermogenesis and endurance capacity were measured. The effects of KME on adipogenic factors were examined in 3T3-L1 cells. Body and epididymal fat pad weights were reduced in KME-treated mice, and histological examination showed an amelioration of fatty liver in KME-treated mice, without an effect on food consumption. KME potently induces mitochondrial activity by activating thermogenesis and improving endurance capacity. KME also inhibited adipogenic factors in vitro. These results demonstrate the inhibitory effects of KME on obesity and NAFLD in mice fed a high-fat diet. The effects appear to be mediated through an enhanced mitochondrial activity. Therefore, KME may be an effective therapeutic candidate for treating obesity and fatty liver caused by a high-fat diet.

B-cell-activating factor is a regulator of adipokines and a possible mediator between adipocytes and macrophages.

3T3-L1 adipocytes express the B-cell-activating factor (BAFF) and three different BAFF receptors (BAFF-Rs). Furthermore, BAFF expression is regulated by inflammatory modulators, such as tumor necrosis factor-α and rosiglitazone. Here we investigated the function of BAFF in 3T3-L1 adipocytes and RAW 264.7 macrophages. We examined adipokine expression in 3T3-L1 adipocytes treated with 10 ng ml(-1) BAFF. We also examined inflammatory molecule expression in RAW 264.7 macrophages treated with 10 or 100 ng ml(-1) BAFF. We examined BAFF expression in the coculture of 3T3-L1 adipocytes and RAW 264.7 macrophages, as well as in white adipose tissue (WAT) of diet-induced obese (DIO) mice. We found that BAFF decreases leptin and adiponectin expression, but increases the expression of proinflammatory adipokines monocyte chemotactic protein-1, interleukin-6 (IL-6), cyclooxygenase-2 (COX-2) and haptoglobin. Coculturing the two cell types resulted in increased BAFF mRNA and protein expression, as well as modulation of BAFF-R mRNA expression in both cell types. These data indicate that BAFF might mediate adipocyte and macrophage interaction. When RAW 264.7 macrophages were treated with BAFF, BAFF-R expression was modulated as in coculture, and nitric oxide synthase and IL-6 expression increased. BAFF expression also increased in WAT of DIO mice. We propose that BAFF can regulate adipokine expression and possibly mediate adipocyte and macrophage interaction.

The probiotic Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 promote cholesterol efflux and suppress inflammation in THP-1 cells.

BACKGROUND: The balance between the rate of cholesterol uptake/accumulation and the rate of cholesterol efflux is reflected in the amount of lipid accumulation in macrophages. Based upon the fact that liver X receptors (LXRs) play a role in cholesterol efflux, we studied the effects of probiotics on cholesterol efflux and anti-inflammatory action in macrophages. We confirmed changes in LXR expression by treatment of LXR-transfected CHO-K1 cells with lactic acid bacteria (LAB), and co-cultured THP-1 cells with LAB to investigate changes in cholesterol efflux and inflammation. RESULTS: The experiment with CHO-K1 cells showed upregulation of LXR-ß by LAB. Treatment of THP-1 cells with LAB promoted LXR expression in THP-1, which eventually led to significant upregulation of ABCA1 and ABCG1 expression. The treatment with live LAB also significantly promoted cholesterol efflux. LAB suppressed expression of interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, which resulted from activation of LXR. CONCLUSION: Our study shows that Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 activated LXR and induced cholesterol efflux by promoting expression of ABCA1 and ABCG1. Both strains also suppressed proinflammatory cytokines including IL-1ß and TNF-α. This study could account for the observation that LAB may block foam cell formation by cholesterol efflux and immune modulation.

Reduction in cholesterol absorption in Caco-2 cells through the down-regulation of Niemann-Pick C1-like 1 by the putative probiotic strains Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 from fermented foods.

Hypercholesterolaemia is a major risk factor related to atherosclerosis, and it may be influenced by our diet. This study addresses the impact of Lactobacillus rhamnosus BFE5264 (isolated from Maasai fermented milk) and Lactobacillus plantarum NR74 (from Korean kimchi) on the control of cholesterol absorption through down-regulation of Niemann-Pick C1-like 1 (NPC1L1) expression. Caco-2 enterocytes were treated with the live, heat-killed (HK) bacteria, bacterial cell wall extracts and metabolites; mRNA level and protein expression were measured. Caco-2 cells showed lower NPC1L1 expression in the presence of the live test strains than the control, elucidating down-regulation of cholesterol uptake, and were compared well with the positive control, L. rhamnosus GG. This effect was also observed with HK bacteria and cell wall fractions but not with their metabolites. The potential of some Lactobacillus strains associated with traditional fermented foods to suppress cholesterol uptake and promote its efflux in enterocytes has been suggested from these data.

Anti-obesity and antioxidative effects of purple sweet potato extract in 3T3-L1 adipocytes in vitro.

The purpose of the current study was to determine the anti-obesity and anti-inflammatory effects of an extract of purple sweet potatoes (PSPs) on 3T3-L1 adipocytes. For this purpose, differentiated 3T3-L1 adipocytes were treated with a PSP extract at concentrations of 1,000, 2,000, and 3,000 µg/mL for 24 hours. Then, we measured the changes in the sizes of the adipocytes, the secretion of leptin, and the mRNA/protein expression of lipogenic, inflammatory, and lipolytic factors after the treatment with the PSP extract. The PSP extract diminished leptin secretion, indicating that growth of fat droplets was suppressed. The extract also suppressed the expression of mRNAs of lipogenic and inflammatory factors and promoted lipolytic action. The antioxidative activity of the PSP extract was also measured using three different in vitro methods: 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, ferric reducing ability potential assay, and chelating activity of transition metal ions. Taken together, our study shows that PSP extract has antilipogenic, anti-inflammatory, and lipolytic effects on adipocytes and has radical scavenging and reducing activity.

Expression of eotaxin in 3T3-L1 adipocytes and the effects of weight loss in high-fat diet induced obese mice.

Eotaxin is an important inflammatory chemokine in eosinophil chemotaxis and activation and, thus, is implicated in asthma. Recently, obesity was associated with an increased prevalence of asthma, but the relationship between obesity and eotaxin expression has only been partially understood in obese mice and human studies. Therefore, we studied the expression patterns of eotaxin in 3T3-L1 preadipocytes/adipocytes to determine whether eotaxin levels are influenced by body weight gain and/or reduction in diet-induced obese mice. First, we investigated eotaxin expression during differentiation in 3T3-L1 adipocytes. Then, we treated 3T3-L1 preadipocytes/adipocytes with tumor necrosis factor-alpha (TNF-α), eotaxin, interleukin (IL)-4, IL-5, or leptin. To examine the effects of weight loss in high-fat diet induced obese mice, we fed C57BL/6 mice a high-fat diet or a normal diet for 26 weeks. Then, half of the high-fat diet group were fed a normal diet until 30 weeks to reduce weight. Epididymal adipose tissue, visceral adipose tissue, serum, and bronchoalveolar fluid of mice were examined for eotaxin expression. The results showed that eotaxin expression levels increased with adipocyte differentiation and that more eotaxin was expressed when the cells were stimulated with TNF-α, eotaxin, IL-4, IL-5, or leptin. An in vivo study showed that eotaxin levels were reduced in visceral adipose tissues when high-fat diet fed mice underwent weight loss. Taken together, these results indicate a close relationship between eotaxin expression and obesity as well as weight loss, thus, they indirectly show a relation to asthma.

Lactobacillus rhamnosus BFE 5264 and Lactobacillus plantarum NR74 Promote Cholesterol Excretion Through the Up-Regulation of ABCG5/8 in Caco-2 Cells.

The effect of two putative probiotic strains, Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74, on the control of cholesterol efflux in enterocytes was assessed by focusing on the promotion of ATP-binding cassette sub-family G members 5 and 8 (ABCG5 and ABCG8). Differentiated Caco-2 enterocytes were treated with live bacteria, heat-killed bacteria, a bacterial cell wall fraction, and metabolites and were subjected to cholesterol uptake assay, mRNA analysis, and protein analyses. Following LXR-transfection by incubation with CHO-K1 cells in DNA-lipofectin added media, the luciferase assay was conducted for LXR analysis. Treatment of Caco-2 cells with L. rhamnosus BFE5264 (isolated from traditional fermented Maasai milk) and L. plantarum NR74 (isolated from Korean kimchi) resulted in the up-regulation of LXR, concomitantly with the elevated expression of ABCG5 and ABCG8. This was associated with the promotion of cholesterol efflux at significantly higher levels compared to the positive control strain L. rhamnosus GG (LGG). The experiment with CHO-K1 cells confirmed up-regulation of LXR-beta by the test strains, and treatment with the live L. rhamnosus BFE5264 and L. plantarum NR74 strains significantly increased cholesterol efflux. Heat-killed cells and cell wall fractions of both LAB strains induced the upregulation of ABCG5/8 through LXR activation. By contrast, LAB metabolites did not show any effect on ABCG5/8 and LXR expression. Data from this study suggest that LAB strains, such as L. rhamnosus BFE5264 and L. plantarum NR74, may promote cholesterol efflux in enterocytes, and thus potentially contribute to the prevention of hypercholesterolemia and atherosclerosis.

The inhibition of inflammatory molecule expression on 3T3-L1 adipocytes by berberine is not mediated by leptin signaling.

In our previous study, we have shown that berberine has both anti-adipogenic and anti-inflammatory effects on 3T3-L1 adipocytes, and the anti-adipogenic effect is due to the down-regulation of adipogenic enzymes and transcription factors. Here we focused more on anti-inflammatory effect of berberine using real time RT-PCR and found it changes expressions of adipokines. We hypothesized that anti-adipogenicity of berberine mediates anti-inflammtory effect and explored leptin as a candidate mediator of this signaling. We studied this hypothesis by western blot analysis, but our results showed that berberine has no effect on the phosphorylations of STAT-3 and ERK which have important roles on leptin signaling. These results led us to conclude that the anti-inflammatory effect of berberine is not mediated by the inhibition of leptin signal transduction. Moreover, we have found that berberine down-regulates NF-kappaB signaling, one of the inflammation-related signaling pathway, through western blot analysis. Taken together, the anti-inflammatory effect of berberine is not mediated by leptin, and berberine induces anti-inflammatory effect independent of leptin signaling.

B cell activation factor (BAFF) is a novel adipokine that links obesity and inflammation.

B cell activation factor (BAFF) is a novel member of the TNF ligand superfamily, mainly produced by myeloid cells. BAFF has been shown to participate in B-cell survival and B- and T-cell maturation. BAFF expression in adipocytes has been recently demonstrated. In the current study, we verified that BAFF expression is increased during adipocyte differentiation. BAFF expression was augmented by TNF-alpha treatment and was decreased by rosiglitazone treatment. BAFF secretion in lean and in ob/ob mice sera were compared and smaller amount of BAFF was secreted in ob/ob mice. mRNA and protein expression were different between epididymal and visceral adipose tissue. BAFF expression was also increased in ob/ob mouse adipose tissue. We sought to identify known BAFF receptors (BAFF-R, BCMA, and TACI) in adipocytes, and determined that all three were present and upregulated during adipocyte differentiation. However, the expression of TACI was distinct from that of BAFF-R and BCMA under TNF-alpha and BAFF ligand treatment. BAFF-R and BCMA expression levels were upregulated under pro-inflammatory conditions, but TACI was reduced. Conversely, BAFF-R and BCMA expression levels were downregulated by rosiglitazone treatment, but TACI was increased. Taken together, our results suggest that BAFF may be a new adipokine, representing a link between obesity and inflammation.

Anti-obesity and hypolipidemic effects of black soybean anthocyanins.

The effect of anthocyanins extracted from black soybean (Glycine max L.) seed coats on body weight, adipose tissue weight, and serum lipids was evaluated in rats fed a high fat diet (HFD). Rats were raised on a normal diet (ND) (based on the AIN-93M diet), HFD (ND supplemented with 16% lard oil), HFD containing 10% black soybean, and HFD containing 0.037% black soybean anthocyanins (equivalent to that in the 10% black soybean diet). Weight gain was significantly lowered in the rats fed HFD plus black soybean anthocyanins compared with the rats fed HFD alone (P < .05) and reversed to the level of the rats fed ND. The black soybean diet also decreased body weight gain compared with the HFD (P < .05). The black soybean anthocyanins-added diet suppressed the HFD-induced weight gain in liver intermediately and tended to decrease the weights of epididymal and perirenal fat pads. The black soybean anthocyanins were also effective in improving the lipid profile. They significantly reduced the levels of serum triglyceride and cholesterol (P < .05), while they markedly increased the high-density lipoprotein-cholesterol concentration, which was decreased in the rats fed HFD (P < .05). These results indicate that the anthocyanins in black soybean seed coats have an anti-obesity effect, which can reverse the effects of HFD on body weight, adipose tissue weight, and serum lipid contents.

Inflammatory gene expression patterns revealed by DNA microarray analysis in TNF-alpha-treated SGBS human adipocytes.

We report here the use of human inflammation arrays to study the inflammatory gene expression profile of TNF-alpha- treated human SGBS adipocytes. Human preadipocytes (SGBS) were induced to differentiate in primary culture, and adipocyte differentiation was confirmed, using Oil Red O staining. We treated the differentiated adipocytes with TNF-alpha, and RNA from differentiated adipocytes with or without TNF-alpha treatment was hybridized to MWG human inflammation arrays to compare expression profiles. Eleven genes were up- or down-regulated in TNF-alpha-treated adipocytes. As revealed by array analysis, among 6 up-regulated genes, only eotaxin-1, monocyte chemoattractant protein-1 (MCP-1), and vascular cell adhesion molecule 1 isoform a precursor (VCAM1) were confirmed by real-time polymerase chain reaction (PCR). Similarly, among 5 down-regulated genes, only IL-1 family member 5 (IL1F5), a disintegrin and metalloprotease with thrombospondin motifs-1 preproprotein (ADAMTS1), fibronectin 1 isoform 1 preprotein (FN1), and matrix metalloproteinase 15 preprotein (MMP15) were confirmed by real-time PCR. There was a substantial increase (50-fold) in eotaxin-1 in response to TNF-alpha. Taken together, we have identified several inflammatory molecules expressed in SGBS adipocytes and discovered molecular factors explaining the relationship between obesity and atherosclerosis, focusing on inflammatory cytokines expressed in the TNF-alpha-treated SGBS cells. Further investigation into the role of these up- or down-regulated cytokine genes during the pathological processes leading to the development of atherosclerosis is warranted.

Isomer-specific effect of conjugated linoleic acid on inflammatory adipokines associated with fat accumulation in 3T3-L1 adipocytes.

The purpose of this study was to examine the isomer-specific effect of conjugated linoleic acid (CLA) on inflammatory markers associated with fat accumulation in cultures of differentiating 3T3-L1 adipocytes. trans-10,cis-12 CLA (t10c12 CLA) reduced leptin secretion and fat accumulation. Linoleic acid (LA) and cis-9,trans-11 CLA (c9t11 CLA) increased them, but not significantly. t10c12 CLA and LA showed similar effects on mRNA expression of inflammatory markers. t10c12 CLA and LA tended to up-regulate the mRNA levels of inflammatory cytokines such as interleukin (IL)-6 (not significantly), tumor necrosis factor (TNF)-alpha, and C-reactive protein (CRP) with no significant change in the secretion of adiponectin, an anti-inflammatory adipokine. However, c9t11 CLA induced no significant change in the mRNA expression of IL-6, TNF-alpha, or CRP, but significantly increased adiponectin secretion. In conclusion, CLA exerted isomer-specific effects on fat accumulation and mRNA expression of inflammatory markers in 3T3-L1 adipocytes. t10c12 CLA up-regulated inflammatory markers in spite of the decreased fat accumulation, and TNF-alpha might be one of the causal factors.

Antiobesity effect of Kochujang (Korean fermented red pepper paste) extract in 3T3-L1 adipocytes.

Kochujang (Korean fermented red pepper paste) is a mixture of fermented soybeans, wheat, and red pepper powder. Kochujang has been reported to reduce body fat gain and lipid levels of adipose tissues and serum in rats. We studied the inhibitory effect of Kochujang on lipid accumulation and investigated the molecular mechanism of the action in 3T3-L1 adipocytes by measuring the expression levels of adipocyte-specific genes by real-time reverse transcription-polymerase chain reaction. When 3T3-L1 adipocytes were treated with Kochujang extract (KE), the sizes of adipocytes and leptin secretion were decreased. Hormone-sensitive lipase (HSL) was transcriptionally up-regulated at 4 hours, and glycerol secretion was increased at both 4 hours and 24 hours. Moreover, mRNA expression levels of both sterol regulatory element-binding protein 1-c (SREBP-1c) and peroxisome proliferator-activated receptor-gamma (PPAR-gamma), which are critical transcription factors for adipogenesis, were markedly down-regulated. Tumor necrosis factor-alpha (TNF-alpha) is reported to impair pre-adipocyte differentiation and induce lipolysis and apoptosis. KE treatment of 3T3-L1 adipocytes decreased TNF-alpha mRNA levels, but had no apparent affect on apoptosis. Taken together, our study shows that Kochujang decreased lipid accumulation in 3T3-L1 adipocytes by inhibiting adipogenesis through down-regulation of SREBP-1c and PPAR-gamma and by stimulation of lipolysis due to increased HSL activity. TNF-alpha might not be involved in the reduction of lipid accumulation by KE.

Berberine reduces the expression of adipogenic enzymes and inflammatory molecules of 3T3-L1 adipocyte.

Berberine (BBR), an isoquinoline alkaloid, has a wide range of pharmacological effects, yet its exact mechanism is unknown. In order to understand the anti-adipogenic effect of BBR, we studied the change of expression of several adipogenic enzymes of 3T3-L1 cells by BBR treatment. First, we measured the change of leptin and glycerol in the medium of 3T3-L1 cells treated with 1 micrometer, 5 micrometer and 10 micrometer concentrations of BBR. We also measured the changes of adipogenic and lipolytic factors of 3T3-L1. In 3T3-L1 cells, both leptin and adipogenic factors (SREBP-1c, C/EBP-alpha, PPAR-gamma, fatty acid synthase, acetyl-CoA carboxylase, acyl-CoA synthase and lipoprotein lipase) were reduced by BBR treatment. Glycerol secretion was increased, whereas expression of lipolytic enzymes (hormone-sensitive lipase and perilipin) mRNA was slightly decreased. Next, we measured the change of inflammation markers of 3T3-L1 cells by BBR treatment. This resulted in the down-regulation of mRNA level of inflammation markers such as TNF-alpha, IL-6, C- reactive protein and haptoglobin. Taken together, our data shows that BBR has both anti-adipogenic and anti-inflammatory effects on 3T3-L1 adipocytes, and the anti-adipogenic effect seems to be due to the down-regulation of adipogenic enzymes and transcription factors.

Dual roles of P2 purinergic receptors in insulin-stimulated leptin production and lipolysis in differentiated rat white adipocytes.

ATP is co-localized with norepinephrine at the sympathetic nerve terminals and may be released simultaneously upon neuronal stimulation, which results in activation of purinergic receptors. To examine whether leptin synthesis and lipolysis are influenced by P2 purinergic receptor activation, the effects of ATP and other nucleotides on leptin secretion and glycerol release have been investigated in differentiated rat white adipocytes. Firstly, insulin-induced leptin secretion was inhibited by nucleotide treatment with the following efficacy order: 3'-O-(4-benzoyl)benzoyl ATP (BzATP) > ATP >> UTP. Secondly, treatment of adipocytes with ATP increased both intracellular Ca(2+) concentration and cAMP content. Intracellular calcium concentration was increased by ATP and UTP, but not BzATP, an effect attributed to phospholipase C-coupled P2Y(2). On the other hand, cAMP was generated by treatment with BzATP and ATPgammaS, but not UTP, indicating functional expression of adenylyl cyclase-coupled P2Y(11) receptors in white adipocytes. Thirdly, lipolysis was significantly activated by BzATP and ATP, which correlated with the characteristics of the P2Y(11) subtype. Taken together, the data presented here suggest that white adipocytes express at least two different types of P2Y receptors and that activation of P2Y(11) receptor might be involved in inhibition of leptin production and stimulation of lipolysis, suggesting that purinergic transmission can play an important role in white adipocyte physiology.