Gum Arabic modifies anti-inflammatory cytokine in mice fed with high fat diet induced obesity

ITC study on the interaction of some bile salts with tragacanth, Arabic, and guar gums with potential cholesterol-lowering ability

Introduction

The urge of designing new safe and natural functional foods to control blood lipids and dispensable without the need of physician supervision, has increased especially after the coming into effect of the recent EU Commission regulation 2022/860, that regulates the consumption of "red yeast rice," made by fermentation of rice with Monascus purpureus, and perceived as a natural functional food, due to a health risk for frail consumers. The results of the present work are a part of the systematic study we are carrying out of the binding ability of some soluble dietary fibers (SDF) from different natural sources toward selected bile salts (BS).

Methods

Measurements were carried out by isothermal titration calorimetry (ITC) with the idea to shed light on the mechanism, if any, by which they show cholesterol-lowering activity.

Results and discussion

Epidemiological studies are sometimes conflicting and offer only hypothesis about the mechanism of action, the most accredited being the reduction of reabsorption of BS in the gut. Previous measurements done on negatively charged pectin and alginate, showed specific binding interaction with monomer NaDC for pectin and no interaction at all for alginate. Chitosan, positively charged and soluble only at low pH, in 100 mM acetate buffer at pH = 3 shows strong exothermic interactions with NaTC and NaTDC. Here we considered two plant exudates (Arabic gum and tragacanth gum) and guar gum, extracted from guar beans, and their interaction with the same bile salts. ITC measurements do not evidence specific interactions between gums and the studied BS, so that their cholesterol lowering ability, if any, is due to a different mechanism very probably bound to the viscosity increase. Moreover, the addition of NaC, the most abundant BS in the bile, at very low concentration (under the cmc) causes a structural change of the solution. The obtained results seem to corroborate the hypothesis that the cholesterol lowering activity is related to the increase in viscosity of guar solution favored by NaC, the major component of the bile.

Soluble Dietary Fibers as Antihyperlipidemic Agents: A Comprehensive Review to Maximize Their Health Benefits

The number of hypercholesterolemic people is increasing rapidly worldwide, with elevated lipid profiles representing a major risk factor of coronary heart diseases. Dietary intervention was shown to improve the lipid profile, thus enhancing the quality of life. Dietary fiber is a nondigestible form of carbohydrates, due to the lack of the digestive enzyme in humans required to digest fiber, and is classified according to its water solubility properties as either soluble (SDF) or insoluble dietary fiber (IDF). Consumption of SDF is associated with several health benefits such as reduced lipid levels, lower blood pressure, improved blood glucose control, improved immune function, and reduced inflammation. SDF has been shown to lower blood cholesterol by several action mechanisms including directly due to the gelling, mucilaginous, and viscous fiber nature, and indirectly due to its fermented products and modulation of the gut microbiome. This review aims to provide a holistic overview on how SDF impacts the lipid profile. We start by providing an overview of the chemical structure of the major SDFs including mucilage, gums (gum arabic and guar gum), pectin, and inulin.

Effects of Gum Arabic (Acacia senegal) Powder on Characteristics of Carcass and Breast Meat Quality Parameters in Male Broiler Chickens

Gum Arabic, one of the soluble fibers, is considered a source of natural prebiotics that can be fermented by the activity of the intestinal microbiota and, therefore, may have a positive effect on the performance, carcass characteristics, and meat quality of broilers. Therefore, the objective of this study was to investigate the effects of gum Arabic on performance, carcass characteristics, physicochemical properties, and quality of broiler breast meat. Six dietary treatments (T1-T5) with a basal diet (CON) containing 0.12%, 0.25%, 0.5%, 0.75%, and 1.0% gum Arabic, respectively. A total of 432 one-day-old male broiler chickens were conducted for 35 days. Performance and carcass characteristics, as well as physical, qualitative, and chemical indicators of breast meat, were evaluated. The results showed that the treatments improved overall performance (p < 0.05), such as body weight, weight gain, feed conversion ratio, and performance index, except for feed intake, which was lower at T1, T2, and T5 than at CON. Carcass characteristics, body components, and breast meat color or initial pH were not affected by dietary treatments (p > 0.05), but ultimate pH (T1 and T2) and color lightness were comparatively lower, and color change (T2-T3) was comparatively higher. Cooking water loss (T2-T4) and shear force (T1-T5) were higher in the treatments. Cohesiveness and resilience were higher in T2, while gumminess and chewiness were lower in T4 and T5. T1 breast meat had higher crude protein content and lower crude fat content, but the other chemical compositions were not affected by the treatments. Some fatty acids in the breast meat were more affected by treatments compared to CON. In conclusion, the present findings showed that gum Arabic (0.12% to 0.75%) has favorable effects on growth performance and some quality indicators of breast meat (such as cooking water loss, shear force, protein, and fat content), especially at the level of 0.12% with no alterations on the carcass characteristics and body components or physical indicators of breast meat.

Induction mechanism of cigarette smoke components (CSCs) on dyslipidemia and hepatic steatosis in rats

Objective

The purpose of this study was to explore the effect of cigarette smoke component (CSC) exposure on serum lipid levels in rats and the underlying molecular mechanism.

Methods

Male SPF-grade SD rats were randomly divided into a control group and a CSC exposure group, with the CSC group being exposed to CSC for 6 weeks. RT–PCR and Western blotting methods were used to detect lipid metabolism gene expression in rats, and 16S RNA gene sequencing was used to detect the gut microbiota in the rat cecum. Rat serum exosomes were prepared and identified, and the interaction of exosomal miR-291a-3p and miR-126a-5p with AMPK and CYP7A1 was detected by a dual luciferase reporter gene assay (DLRG).

Results

Serum indicators, including cholesterol levels and trimethylamine oxide (TMAO) content, were significantly affected in the CSC exposure group compared with the control group (P < 0.05), and the expression levels of adenylate-activated protein kinase (AMPK), acetyl-coenzyme A carboxylase (ACC) and HMG-CoA reductase (HMG-CoAR) genes were significantly increased (P < 0.05) in the liver, while the expression level of cholesterol 7α-hydroxylase (CYP7A1) was markedly decreased (P < 0.01). 16S rRNA gene sequencing of the gut microbiota in the rat cecum showed that the abundance of Firmicutes in the CSC group increased significantly at the phylum level, while the abundances of Bacteroidota and Spirochaetota were reduced significantly (P < 0.01). The relative abundance of Romboutsia, Turicibacter, and Clostridium sensu stricto increased significantly (P < 0.01), and the relative abundance of Prevotella, Muribaculaceae_norank, Lachnospiraceae NK4A136 group, Roseburia, Treponema, and Ruminococcus significantly decreased (P < 0.01) at the genus level. In addition, the exosome miR-291a-3p and miR-126a-5p levels were markedly regulated by CSC exposure (P < 0.01). The interactions of miR-291a-3p and miR-126a-5p with AMPK and CYP7A1 mRNA were also validated by the DLRG method.

Conclusions

In summary, the rat dyslipidemia induced by CSC exposure may be related to the interference of gut microbiota structure and interaction of miRNAs from serum exosomes with target mRNAs, which further regulated AMPK-ACC/CYP7A1 signaling in rats.

Use of High-Performance Liquid Chromatography/Electrospray Ionization Mass Spectrometry for Structural Characterization of Bioactive Compounds in the Olive Root Bark and Wood of Chemlali Cultivar

This report aims to provide complete knowledge on the polyphenol composition and biological activities of the olive tree. The extraction of the root bark and wood of Olea europaea. L (Chemlali cultivar) was realized by solid-liquid ethanolic extraction, whose analysis was conducted via high-performance liquid chromatography equipped with photodiode array detection and mass spectrometry (HPLC-ESI-DAD and MS/MS). Moreover, radical scavenging and antibacterial activities were determined. The results present a total of 14 phenolic compounds belonging mainly to secoiridoid and flavonoid subclasses. Oleuropein was found to be the most abundant compound at an amount of up to 7000 mg/kg followed by ligstroside and oleuropein derivatives. In addition, we found oleocanthal at a great amount (2115 mg/kg). Higher individual polyphenolic concentrations were recorded in root wood extracts compared to bark ones, except for the flavonoid group. Likewise, the total phenolic compound contents increased in the olive root wood. This trend was reflected in biological activities. In fact, root wood extracts exert more important antioxidant and antibacterial activities than bark extracts due to their high bioactive compounds.

The effect of combining basil seeds and gum Arabic on the healing process of experimental acetic acid-induced ulcerative colitis in rats

Background & aim

Ulcerative colitis (UC) is a chronic recurrent inflammatory disease of the large intestine and rectum that oxidative stress and severe inflammation are the main features of this disease. Previous studies have shown that separate consumption of basil and gum arabic can reduce inflammation and oxidative stress. The aim of the study was evaluating the effect of treatment with basil seeds given together with gum arabic on healing, inflammation and oxidative stress in the course of experimental colitis in rats.

Experimental procedure

A total number of 50 male rats were used, randomly assigned to five groups of 10 rats each. Colitis was induced in rats by enemas with 4% solution od acetic acid. Four days after induction of colitis, rats were treated for next 4 days with saline or combination of basil seeds plus gum arabic (1 mg/kg) or sulfasalazine (100 mg/g) rectally. The experiment was terminated after last dose of treatment. Rats without induction of colitis were used as a sham group.

Results

Acetic acid-induced colitis increased the macroscopic and histopathological damage scores of the colon as well as colon levels of MDA(Malondialdehyde), MPO(Myeloperoxidase), TNFα(Tissue necrosis factor α), IL6 (Interleukin 6)and IL17(Interleukin 17) and decreased SOD(Superoxide Dismutase), GPx (Glutathione Peroxidase) and IL10 (Interleukin 10) levels compared with the control group(P < 0.001). Treatment with basil and gum arabic reduced macroscopic and histopathological damage scores (P < 0.01) of the colon, MDA, MPO, TNFα, IL6(P < 0.001) and IL17 (P < 0.01) levels of the colon and increased SOD, GPx and IL10 levels compared to the colitis group (P < 0.01).

Conclusion

Rectal administration of combination of basil seeds plus gum arabic after induction of colitis, exhibits antioxidant and anti-inflammatory effects, and accelerates the healing of the colon in experimental colitis evoked by acetic acid.

Upregulation of miR-33 and miR-155 by gum acacia mitigates hyperlipidaemia and inflammation but not weight increase induced by Western diet ingestion in mice

OBJECTIVE

This study, for the first time, investigates the effect of gum acacia (GA) on the expression of miR-33 and miR-155 and its association with the obesity and inflammation induced by Western diet (WD) consumption in mice.

METHODS

Animals were divided into: normal diet (ND) group, WD group, GA group and GA + WD group.

RESULTS

The WD group exhibited higher total body, liver, visceral fat weights, blood total cholesterol, triglycerides and glucose levels compared to ND group. The liver tissues showed severe inflammation and degeneration with higher hepatic TNF-α level. Interestingly, GA + WD group showed a decrease in the biochemical parameters and hepatic TNF-α level but had no effect on the weight increase. It also showed a significant upregulation of miR-33 and miR-155 compared to WD group.

CONCLUSIONS

GA mitigated the hyperlipidaemia and inflammation but not weight increase induced by WD ingestion via upregulation of miR-33 and miR-155 while reducing TNF-α level.