Modulatory effect of green coffee bioactives on high-fat diet-induced obesity in C57BL6 mice model

OBJECTIVES

The aim of the present study was to determine the efficacy of green coffee bioactives in ameliorating the effects of high-fat diet (HFD)-induced obesity through in vitro and in vivo assessments.

METHODS

Green coffee extract (GCE) was obtained by implementing a novel green extraction technique. The efficacy of GCE to inhibit in vitro pancreatic amylase and lipase was evaluated. Further, in vivo studies were conducted using a C57BL6 mice model grouped as starch-fed diet control, HFD control, HFD + positive control, HFD + GCE (100 mg/kg body weight), and HFD + GCE (200 mg/kg body weight). Animal body weight, diet intake, and fecal fat excretion were measured during the feeding period. On completion of the experiment, blood serum was collected for biochemical analysis, and organs were harvested for assessing the obesity-related biomarkers.

RESULTS

The obtained GCE was enriched with polyphenols and alkaloids. GCE led to significant (P < 0.05) in vitro inhibition of pancreatic amylase and lipase. GCE supplementation considerably prevented weight gain in treated groups post-consumption of HFD. It also led to increased fecal fat excretion and regulated the high-fat-mediated blood glucose levels. GCE effectively modulated the blood lipid profile, morphology of adipose and liver tissues, and liver antioxidant defense enzymes and resulted in hepatoprotective effects. It also downregulated the genes associated with lipid biosynthesis.

CONCLUSIONS

GCE exhibits promising results in suppressing the consequences associated with HFD-induced obesity. It has the potential to be incorporated into food products benefiting consumer health and food industries.

Chlorogenic acid in green bean coffee on body weight: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Supplemental green bean coffee extract (GBCE) with caffeine has been shown to prevent weight gain. There are different dosages of GBCE that contain chlorogenic acid (CGA), and the data for their effectiveness in preventing weight gain (500 mg/day) is currently out of date. To better understand the effects of GBCE containing CGA on body weight, the present study sets out to perform a systematic review and meta-analysis of these studies.

METHODS

Using electronic databases, including Scopus, Embase, PubMed, and Cochrane Library databases, literature was searched up to October 13, 2022. For the meta-analysis examining the impact of GBCE containing CGA (500 mg/day) on body weight with a random-effects model, the randomized controlled trials (RCTs) were considered. We calculated weighted mean differences and 95% confidence intervals (CIs). To gauge study heterogeneity, the Cochran Q statistic and I-squared tests (I2) were employed.

RESULTS

The meta-analysis includes three RCTs with 103 individuals (case = 51, control = 52). The combined findings of GBCE with CGA at least 500 mg/day result in body weight reduction (WMD: - 1.30 and 95% CI: - 2.07 to - 0.52, p = 0.001) without study heterogeneity (I2 = 0%, p = 0.904) and without publication bias estimated using Egger's and Begger's test (p = 0.752 and p = 0.602, respectively).

CONCLUSIONS

According to the meta-analysis, GBCE with CGA 500 mg/day lowers body weight. Nevertheless, despite its limited sample size and short-term study, this study was successful. Long-term research on the effectiveness and safety of GBCE and CGA on body weight require more clinical trials.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021254916.

Green coffee extract modifies body weight, serum lipids and TNF-α in high-fat diet-induced obese rats

OBJECTIVE

Currently, there are many efforts to find functional nutrients for obesity management, and the green coffee extract is a potential candidate. This study aimed to examine the effect of low dose administration of  green coffee extract on body weight, serum lipids, and TNF-α level in high-fat diet-induced obese rats.

RESULTS

Administration of green coffee extract to high-fat diet-induced obese male Wistar rats (Rattus norvegicus) reduced body weight, total serum cholesterol, and triglyceride at the dose of 10, 20, and 40 mg/kg BW/day; lowered serum LDL-cholesterol at the treatment dose of 20 mg/kg BW/day (p < 0.05). The effective dose to decrease serum TNF-α level was 40 mg/kg BW/day, while the effective dose to improve the lipid profile was 10 mg/kg BW/day. These results support the potential use of green coffee extract as a functional nutrient in the management of obesity.

Investigation of the effect of coffee on body weight, serum glucose, uric acid and lipid profile levels in male albino Wistar rats feeding on high-fructose diet

Coffee is one of the most commonly consumed beverages in the worldwide and is assumed to have protective effects against metabolic syndrome. The present study was aimed at investigating the effect of coffee on body weight, serum glucose, uric acid and lipid profile levels in male albino Wistar rats feeding on high fructose diet. A post-test experimental study was conducted on a total of 30 (9–10 weeks old) male albino Wistar rats. The rats were divided into 6 groups: group I (normal control)-fed on standard chow and plain tap water only; group II (fructose control)-fed on standard chow and 20% of fructose solution; group III–VI (treatment groups)-fed on standard chow, 20% of fructose solution and treated with 71, 142, 213 and 284 mg/kg body weight/day of coffee respectively for six weeks. At the end, body weight, serum glucose, uric acid and lipid profile levels were investigated. Data was entered and cleared by epi-data software version 3.1 and analyzed by one way ANOVA followed by Tukey post hoc multiple comparison tests using SPSS V. 23.00. Statistical significance was considered at p < 0.05. The results showed that body weight, fasting serum glucose and uric acid levels significantly lowered in rats treated with 213 (p = 0.047; 0.049; 0.026) and 284 (p = 0.035; 0.029; 0.010) mg/kg body weight/day of coffee compared to fructose control group. Fasting serum triglycide (TG) and low density lipoprotein (LDL-C) levels showed significant reduction in rats treated with 284 mg/kg body weight/day of coffee as compared to fructose control group (p = 0.031; 0.046) respectively. In conclusion, treating rats with coffee decreased body weight, fasting serum glucose, uric acid, TC, TG and LDL-C, and increased HDL-C in a dose dependent manner in rats feeding on high fructose diet, suggesting that coffee consumption may be helpful in ameliorating metabolic syndrome.

The influence of green coffee bean extract supplementation on blood glucose levels: A systematic review and dose-response meta-analysis of randomized controlled trials

Studies regarding the influence of green coffee extract (GCE) on blood glucose levels are conflicting. Thus, we sought to conduct a meta-analysis and systematic review of all available randomized controlled trials (RCTs) to quantify the effects of GCE and CGA intervention on blood glucose and insulin levels. We performed systematic online searches in Scopus, Web of science, and PubMed databases, from inception to July 2019. Data were combined analyzed using a random effects model (Der Simonian-Laird method) and reported as weighted mean differences (WMD). Ten trials reported the influences of GCE on FBS and insulin and were subsequently entered into the meta-analysis. Combined results highlighted that FBS was significantly altered after GCE consumption (WMD: -1.791 mg/dl, 95% CI -3.404, -0.177), with no significant heterogeneity among the studies (I² = 35.0%, p = .128). However, overall results demonstrated that GCE administration did not result in any significant alteration in insulin levels (WMD: -0.925 μU/ml, 95% CI:-1.915, 0.064), with significant heterogeneity found across studies (I² = 87.9%). In sub-group analysis, insulin levels were significantly reduced when GCE was supplemented in dosages of ≥400 mg/day (WMD:-1.942 mg/dl, 95% CI:-1.184, -0.975; I² = 0.0%). The results of present study support the use of GCE for the enhancement of blood glucose, while subgroup analysis highlighted significant improvements in insulin levels when GCE is supplemented in doses ≥400 mg/day.

The effects of green coffee bean extract supplementation on lipid profile in humans: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIM

This systematic review and meta-analysis aimed to assess the effects of green coffee bean extract (GCBE) supplementation on lipid profile in adults.

METHODS AND RESULTS

The PubMed/Medline, Scopus, Web of sciences, and Google Scholar were systematically searched for randomized controlled trials available in English and published before February 2019. The meta-analysis was conducted using fixed effects models, and between-study heterogeneity was assessed by Cochran's Q test and I². A total of 17 effect sizes were included in the meta-analysis. Combined effect sizes on serum total cholesterol concentrations revealed significant effects of GCBE supplementation on serum total cholesterol [weighted mean difference (WMD): -4.51 mg/dL, 95% confidence interval (CI): -6.89, -2.12, p < 0.001], low density lipoprotein-cholesterol (LDL-C) (WMD: -4.38 mg/dL, 95% CI: -6.44, -2.31, p < 0.001), and high density lipoprotein-cholesterol (HDL-C) (WMD: 2.63 mg/dL, 95% CI: 2.20, 3.07, p < 0.001) compared to controls. Nevertheless, no significant changes were observed in serum triglycerides levels (WMD: -4.34 mg/dL, 95% CI: -9.00, 0.32, p = 0.068).

CONCLUSION

The evidence from available studies suggests that the GCBE supplementation leads to significant reductions in total cholesterol, HDL-C, and LDL-C levels, and has modest, but, non-significant effects on triglycerides levels.

In Vivo Effects of Salbutamol Residues on Blood Lipid, Lung Structure, Gene Expression, and Gut Microorganism Composition

Salbutamol (SAL), one of the prohibited veterinary drugs, has been proven to be harmful to animals, but very few studies reported the underlying mechanism of actions and the effects after SAL intake. In this study, Ba-Ma minipigs were used as the animal model to demonstrate the impacts of SAL residues on blood lipid and the lung bronchial structures and the regulation of gene expression and gut microorganism population. The results showed that (1) SAL decreased the indexes of serum lipid and organ, (2) SAL widely retained in various tissues and organs, (3) the lung bronchial expanded under the influence of SAL, (4) the gene expression of growth-related ghrelin has increased, and (5) the residues of SAL affected the composition of gut microorganism population, which could be associated with the mechanism of action of SAL on pig. The findings suggest that SAL could be harmful to minipigs by altering the blood lipid, bronchial morphology, gastric mucosal gene expression, and the gut microorganism population.

The effect of green-coffee extract supplementation on obesity: A systematic review and dose-response meta-analysis of randomized controlled trials

BACKGROUND

Given that the most recent systematic review investigating Green-Coffee Extract (GCE) as a weight loss facilitator was nearly a decade ago and that the authors reported there no consensus on the effect of GCE/CGA (Chlorogenic acids) on body composition indices, a comprehensive systematic review and dose-response meta-analysis of all available randomized controlled trial (RCTs) was undertaken to examine the effect of GCE and CGA intervention on body weight (BW), body mass index (BMI) and waist circumference (WC) in adults.

METHODS

We conducted a systematic search of all available randomized controlled trials (RCTs) performed up to June 2019 in the following electronic databases: PubMed, Scopus and Google Scholar. RCTs that investigated the effect GCE/CGA Supplementation on BW, BMI and WC in adults were included for final analysis. The pooled weight mean difference (WMD) of included studies was estimated using a random-effects model.

RESULTS

A total of 13 articles with 16 RCTs were included in the meta-analysis. Results revealed significant reduction in BMI (WMD: -0.403 kg/m², 95% CI: -0.800, -0.005, p = 0.047) and no significant change in BW (WMD: -0.585 kg, 95% CI: -1.498, 0.329, p = 0.210) and WC (WMD: -0.847 cm, 95% CI: -1.764, 0.071, p = 0.070). In the subgroup analysis, studies that were conducted on baseline BMI ≥25 kg/m² revealed a significant greater reduction in body weight and BMI than those performed on baseline BMI <25 kg/m². Moreover, short supplementation periods of less than 4 weeks had no effect.

CONCLUSION

The results of current meta-analysis study support the use of GCE supplementation for the improvement of obesity indices, with sub-group analysis highlighting greater improvements in individuals with a starting BMI ≥25 kg/m².

The Interaction between Coffee: Caffeine Consumption, UCP2 Gene Variation, and Adiposity in Adults-A Cross-Sectional Study

Background

Coffee is suggested as an alternative option for weight loss but the relationship between coffee consumption and adiposity in population-based studies is still controversial. Therefore, this study was aimed at evaluating the relationship between coffee intake and adiposity in adults and to test whether uncoupling protein 2 (UCP2) gene variation was able to affect this relationship.

Methods

This was a cross-sectional study conducted in male and female adults living in the urban area of Yogyakarta, Indonesia. Adiposity was determined based on body weight, body mass index (BMI), percent body fat, and waist and hip circumference. Data on coffee consumption and other dietary components were collected using a semiquantitative food frequency questionnaire along with other caffeine-containing beverages such as tea, chocolate, and other beverages. The -866 G/A UCP2 gene variation was analyzed using polymerase chain reaction-restriction fragment length polymorphism. The correlation between coffee intake and adiposity was tested using linear regression test with adjustment for sex, age, energy intake, table sugar intake, and total caffeine intake.

Results

In all subjects, coffee intake was inversely correlated with body weight (β = -0.122, p=0.028), BMI (β = -0.157, p=0.005), and body fat (β = -0.135, p=0.009). In subjects with AA + GA genotypes, coffee intake was inversely correlated with body weight (β = -0.155, p=0.027), BMI (β = -0.179, p=0.010), and body fat (β = -0.148, p=0.021). By contrast, in subjects with GG genotype, coffee intake was not correlated with body weight (β = -0.017, p=0.822), BMI (β = -0.068, p=0.377), and body fat (β = -0.047, p=0.504).

Conclusion

We showed that coffee intake was negatively correlated with adiposity, and this was independent of total caffeine intake. Additionally, we showed that the -866 G/A UCP2 gene variation influences the relationship between coffee intake and adiposity.

Caffeine adsorption of montmorillonite in coffee extracts

The growth in health-conscious consumers continues to drive the demand for a wide variety of decaffeinated beverages. We previously developed a new technology using montmorillonite (MMT) in selective decaffeination of tea extract. This study evaluated and compared decaffeination of coffee extract using MMT and activated carbon (AC). MMT adsorbed caffeine without significant adsorption of caffeoylquinic acids (CQAs), feruloylquinic acids (FQAs), dicaffeoylquinic acids (di-CQAs), or caffeoylquinic lactones (CQLs). AC adsorbed caffeine, chlorogenic acids (CGAs) and CQLs simultaneously. The results suggested that the adsorption selectivity for caffeine in coffee extract is higher in MMT than AC. The caffeine adsorption isotherms of MMT in coffee extract fitted well to the Langmuir adsorption model. The adsorption properties in coffee extracts from the same species were comparable, regardless of roasting level and locality of growth. Our findings suggest that MMT is a useful adsorbent in the decaffeination of a wide range of coffee extracts.

The potential effects of chlorogenic acid, the main phenolic components in coffee, on health: a comprehensive review of the literature

Chlorogenic acid (CGA), an important biologically active dietary polyphenol, is produced by certain plant species and is a major component of coffee. Reduction in the risk of a variety of diseases following CGA consumption has been mentioned in recent basic and clinical research studies. This systematic review discusses in vivo animal and human studies of the physiological and biochemical effects of chlorogenic acids (CGAs) on biomarkers of chronic disease. We searched PubMed, Embase, Amed and Scopus using the following search terms: ("chlorogenic acid" OR "green coffee bean extract") AND (human OR animal) (last performed on April 1st, 2015) for relevant literature on the in vivo effects of CGAs in animal and human models, including clinical trials on cardiovascular, metabolic, cancerogenic, neurological and other functions. After exclusion of editorials and letters, uncontrolled observations, duplicate and not relevant publications the remaining 94 studies have been reviewed. The biological properties of CGA in addition to its antioxidant and anti-inflammatory effects have recently been reported. It is postulated that CGA is able to exert pivotal roles on glucose and lipid metabolism regulation and on the related disorders, e.g. diabetes, cardiovascular disease (CVD), obesity, cancer, and hepatic steatosis. The wide range of potential health benefits of CGA, including its anti-diabetic, anti-carcinogenic, anti-inflammatory and anti-obesity impacts, may provide a non-pharmacological and non-invasive approach for treatment or prevention of some chronic diseases. In this study, the effects of CGAs on different aspects of health by reviewing the related literatures have been discussed.

Exhaustive Qualitative LC-DAD-MSn Analysis of Arabica Green Coffee Beans: Cinnamoyl-glycosides and Cinnamoylshikimic Acids as New Polyphenols in Green Coffee

Coffee is one of the most consumed beverages in the world, due to its unique aroma and stimulant properties. Although its health effects are controversial, moderate intake seems to be beneficial. The present work deals with the characterization and quantification of polyphenols and methylxanthines in four Arabica green coffee beans from different geographical origins. The antioxidant activity was also evaluated. Forty-three polyphenols (cinnamic acid, cinnamoyl-amide, 5 cinammoyl-glycosides, and 36 cinnamate esters) were identified using LC-MSⁿ. Among these, cinnamate esters of six different chemical groups (including two dimethoxycinnamoylquinic acid isomers, three caffeoyl-feruloylquinic acid isomers, caffeoyl-sinapoylquinic acid, p-coumaroyl-feruloylquinic acid, two caffeoylshikimic acid isomers, and trimethoxycinnamoylshikimic acid) in addition to five isomers of cinnamoyl-glycosides called caffeoyl-2,7-anhydro-3-deoxy-2-octulopyranosic acid (CDOA) are described for the first time in Arabica green coffee beans. Moreover, 38 polyphenols (6-7% w/w) and 2 methylxanthines (1.3% w/w) were quantified by HPLC-DAD. Caffeoylquinic was the most abundant group of compounds (up to 85.5%) followed by dicaffeoylquinic and feruloylquinic acids (up to 8 and 7%, respectively) and the newly identified cinnamoyl-glycosides (CDOA) (up to 2.5%). Caffeine was the main methylxanthine (99.8%), with minimal amounts of theobromine (0.2%). African coffees (from Kenya and Ethiopia) showed higher polyphenolic content than American beans (from Brazil and Colombia), whereas methylxanthine contents varied randomly. Both phenols and methylxanthines contributed to the antioxidant capacity associated with green coffee, with a higher contribution of polyphenols. We conclude that green coffee represents an important source of polyphenols and methylxanthines, with high antioxidant capacity.

Influence of coffee genotype on bioactive compounds and the in vitro capacity to scavenge reactive oxygen and nitrogen species

The influence of green coffee genotype on the bioactive compounds and the in vitro antioxidant capacity against the principal reactive oxygen (ROO(•), H2O2, HO(•), and HOCl) and nitrogen (NO(•) and ONOO(-)) species of biological relevance was investigated. This is the first report on the capacity of green coffee to scavenge H2O2, HOCl, and NO(•). Variations in the contents of total chlorogenic acids (22.9-37.9 g/100 g), cinnamoyl-amino acid conjugates (0.03-1.12 g/100 g), trigonelline (3.1-6.7 g/100 g), and caffeine (3.9-11.8 g/100 g) were found. Hydrophilic extracts of Coffea canephora and Coffea kapakata were the most potent scavengers of ROO(•), H2O2, HO(•), NO(•), and ONOO(-) due to their chlorogenic acid contents, which were, on average, 30% higher than those found in Coffea arabica and Coffea racemosa. The results showed that genotype is a determinant characteristic in the bioactive compound contents and consequently in the antioxidant capacity of green coffee.

Decaffeinated green coffee bean extract attenuates diet-induced obesity and insulin resistance in mice

This study investigated whether decaffeinated green coffee bean extract prevents obesity and improves insulin resistance and elucidated its mechanism of action. Male C57BL/6N mice (N = 48) were divided into six dietary groups: chow diet, HFD, HFD-supplemented with 0.1%, 0.3%, and 0.9% decaffeinated green coffee bean extract, and 0.15% 5-caffeoylquinic acid. Based on the reduction in HFD-induced body weight gain and increments in plasma lipids, glucose, and insulin levels, the minimum effective dose of green coffee bean extract appears to be 0.3%. Green coffee bean extract resulted in downregulation of genes involved in WNT10b- and galanin-mediated adipogenesis and TLR4-mediated proinflammatory pathway and stimulation of GLUT4 translocation to the plasma membrane in white adipose tissue. Taken together, decaffeinated green coffee bean extract appeared to reverse HFD-induced fat accumulation and insulin resistance by downregulating the genes involved in adipogenesis and inflammation in visceral adipose tissue.

Lipolytic activity of Svetol®, a decaffeinated green coffee bean extract

The beneficial health effects of chlorogenic acids (CGAs), major components of coffee beans, are well known and have been attributed to multiple mechanisms of action. However, the lipolytic activity of CGAs does not appear to have been reported. We studied the effects of varying concentrations of Svetol®, a decaffeinated green coffee bean extract enriched in CGAs, on the liberation of free fatty acids from human adipocytes following short-term (2 h) and long-term (192 h) exposure. The results showed that although lipolytic activity observed following short-term incubation could be tentatively linked to residual caffeine traces in the sample, longer-term exposure clearly showed the effects of Svetol® on release of free fatty acids, and this effect was not due to caffeine. The results of this study provide a further mechanism by which to explain the long-term health benefits of CGAs and Svetol®.

Determination of multiple mycotoxins in dietary supplements containing green coffee bean extracts using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS)

An ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the determination of 34 mycotoxins in dietary supplements containing green coffee bean (GCB) extracts was developed, evaluated, and used in the analysis of 50 commercial products. A QuEChERS-like procedure was used for isolation of target analytes from the examined matrices. Average recoveries of the analytes were in the range of 75-110%. The precision of the method expressed as relative standard deviation was below 12%. Limits of detection (LODs) and limits of quantitation (LOQs) ranged from 1.0 to 50.0 μg/kg and from 2.5 to 100 μg/kg, respectively. Due to matrix effects, the method of standard additions was used to ensure accurate quantitation. Ochratoxin A, ochratoxin B, fumonisin B1 and mycophenolic acid were found in 36%, 32%, 10%, and 16% of tested products, respectively. Mycotoxins occurred in the following concentration ranges: ochratoxin A, <1.0-136.9 μg/kg; ochratoxin B, <1.0-20.2 μg/kg; fumonisin B1, <50.0-415.0 μg/kg; mycophenolic acid, <5.0-395.0 μg/kg. High-resolution mass spectrometry operated in full MS and MS/MS mode was used to confirm the identities of the reported compounds.