Novel putative causal mutations associated with fat traits in Nellore cattle uncovered by eQTLs located in open chromatin regions

Intramuscular fat (IMF) and backfat thickness (BFT) are critical economic traits impacting meat quality. However, the genetic variants controlling these traits need to be better understood. To advance knowledge in this area, we integrated RNA-seq and single nucleotide polymorphisms (SNPs) identified in genomic and transcriptomic data to generate a linkage disequilibrium filtered panel of 553,581 variants. Expression quantitative trait loci (eQTL) analysis revealed 36,916 cis-eQTLs and 14,408 trans-eQTLs. Association analysis resulted in three eQTLs associated with BFT and 24 with IMF. Functional enrichment analysis of genes regulated by these 27 eQTLs revealed noteworthy pathways that can play a fundamental role in lipid metabolism and fat deposition, such as immune response, cytoskeleton remodeling, iron transport, and phospholipid metabolism. We next used ATAC-Seq assay to identify and overlap eQTL and open chromatin regions. Six eQTLs were in regulatory regions, four in predicted insulators and possible CCCTC-binding factor DNA binding sites, one in an active enhancer region, and the last in a low signal region. Our results provided novel insights into the transcriptional regulation of IMF and BFT, unraveling putative regulatory variants.

The "crosstalk" between microbiota and metabolomic profile in high-fat-diet-induced obese mice supplemented with Bletilla striata polysaccharides and composite polysaccharides

The potential prebiotic feature of Bletilla striata polysaccharides (BSP) has been widely accepted, while the beneficial effect of BSP on high-fat-diet-induced obesity is unclear. Moreover, the "crosstalk" between microbiota and metabolomic profile in high-fat-diet-induced obese mice supplemented with BSP still need to be further explored. The present study attempted to illustrate the effect of BSP and/or composite polysaccharides on high-fat-diet-induced obese mice by combining multi-matrix (feces, urine, liver) metabolomics and gut microbiome. The results showed that BSP and/or composite polysaccharides were able to reduce the abnormal weight gain induced by high-fat diet. A total of 175 molecules were characterized by proton nuclear magnetic resonance (1H NMR) in feces, urine and liver, suggesting that multi-matrix metabolomics could provide a comprehensive view of metabolic regulatory mechanism of BSP in high-fat-diet-induced obese mice. Several pathways were altered in response to BSP supplementation, mainly pertaining to amino acid, purine, pyrimidine, ascorbate and aldarate metabolisms. In addition, BSP ameliorated high-fat-diet-induced imbalanced gut microbiome, by lowering the ratio of Firmicutes/Bacteroidetes. Significant correlations were illustrated between particular microbiota's features and specific metabolites. Overall, the anti-obesity effect of BSP could be attributed to the amelioration of the disorders of gut microbiota and to the regulation of the "gut-liver axis" metabolism.

Starch-ascorbyl palmitate inclusion complex, a type 5 resistant starch, reduced in vitro digestibility and improved in vivo glycemic response in mice

The prevalence of type 2 diabetes (T2D) has become a major public health concern worldwide. Slowly digested or indigestible carbohydrates such as resistant starch (RS) are associated with a low glycemic index (GI) and the decreased risk of developing T2D. Recently, starch inclusion complexes (ICs) have raised attention due to their thermally stable structure and high RS content. In this study, starch-ascorbyl palmitate (AP) ICs were produced using two different methods with hydrothermal treatments performed, and their in vitro digestion kinetics and in vivo glycemic response in C57BL/6J mice were investigated to determine their potential as a new type of RS, i.e., RS5. After treatments of annealing followed by acid hydrolysis (ANN-ACH), IC samples produced by both methods retained V-type crystalline structure. Either in their raw or treated conditions, V6h-AP ICs prepared using the "empty" V-type method exhibited a more favorable hydrolysis pattern as compared to its counterpart produced by the DMSO method in terms of a lower hydrolysis rate and equilibrium concentration (C∞) (p < 0.05). From the in vitro results, the ANN-ACH treated V6h-AP IC exhibited an estimated GI (eGI) value of 54.83, falling within the range of low GI foods and was the lowest among all tested samples (p < 0.05). Consistent with the in vitro digestion kinetics, the in vivo results showed that mice fed with ANN-ACH V6h-AP IC exhibited a modest glycemic response as evidenced by the lowest increase in postprandial blood glucose and AUC blood glucose (p < 0.05). In addition, the in vivo GI of the ANN-ACH V6h-AP IC (39.53) was the lowest among all the sample treatments and was even lower than that of the RS2 comparison (56, p < 0.05), indicating its more pronounced effect in modulating the postprandial glycemic response in mice and great potential as a new RS5.

Effects of microwave and conventional heating on physicochemical, digestive, and structural properties of debranched quinoa starch-oleic acid complexes with different water addition

BACKGROUND

A starch-lipid complex is a new type of resistant starch, which is of great importance for the prevention of chronic diseases such as diabetes. Most starch-lipid complexes usually need to be treated by heating to make them suitable for a variety of applications, and starch-based foods are generally not edible without a heat-treatment process. However, the digestion and structural properties of the starch-lipid complex will be changed after heating. In this study, microwave and conventional heating were used to treat debranched quinoa starch-oleic acid complexes (DQS-OA) with different water addition conditions, and the effects of the two methods on the physicochemical, digestive, and structural properties of DQS-OA were compared.

RESULTS

The results of in vitro digestibility showed that the resistant starch content (235.34-269.55 g kg^-1 ) of the conventional heating-treated samples was significantly higher than that the microwave-treated samples (141.51-157.99 g kg^-1 ). Moreover, after microwave treatment, the short-range molecular order and crystalline structure of DQS-OA were destroyed and the particle size became smaller. In contrast, the thermal stability, enthalpy, and crystallinity of the complexes after conventional heating were improved. The ratio at 1047/1022 cm^-1 of complexes has also been increased.

CONCLUSION

This study demonstrated that conventional water-bath heating was better than microwave heating in increasing digestion resistance, improving the short-range and long-range molecular order, and promoting the formation of DQS-OA. With an increase in water addition, the influence of microwave or water-bath treatment on the properties of DQS-OA became greater. © 2022 Society of Chemical Industry.

Effects of NaCl and sucrose on the structural and functional properties of debranched quinoa starch-oleic acid complexes under baking

The effects of different dosage of NaCl and sucrose on the structural and functional properties of debranched quinoa starch-oleic acid complexes (DQS-OA) under baking were investigated. The results showed that the resistant starch content of the baked DQS-OA increased by 17.15 % than DQS-OA. The addition of NaCl destroyed the thermal stability, short-range molecular order and crystalline structure of the complexes. The results of particle size, SEM and amylose content showed that NaCl accelerated the degradation of starch granules, which reduced the enzyme resistance of starch. In contrast, the enthalpy (7.28 J/g-7.78 J/g) and crystallinity (54.29 %-56.69 %) of the samples with sucrose significantly increased, and the molecular structure of the complexes became more ordered. Furthermore, with the increase of sucrose concentration, the resistant starch content also increased from 28.80 % to 31.41 %.

Naturally cultured high resistant starch rice improved postprandial glucose levels in patients with type 2 diabetes: A randomized, double-blinded, controlled trial

Objective

To assess the effect of a novel naturally cultured rice with high resistant starch (RS) on postprandial glycemia in patients with type 2 diabetes compared to ordinary rice.

Design

This study is a randomized, double-blinded controlled trial.

Methods

Patients with type 2 diabetes were recruited, and postprandial glucose levels were measured at 5-time points after the ingestion of one of two types of cooked rice in random order. Paired t-tests were used to compare postprandial blood glucose changes and increment areas under the blood glucose curve between high-RS rice and ordinary rice.

Results

The increments of the postprandial blood glucose levels for high-RS rice were significantly lower than that for ordinary rice, i.e., 2.80 ± 1.38 mmol/L vs. 3.04 ± 1.50 mmol/L (P = 0.043) and 3.94 ± 2.25 mmol/L vs. 4.25 ± 2.29 mmol/L (P = 0.036) at 30 min and 60 min, respectively. The incremental areas under the blood glucose curve for high-RS rice were also significantly lower than that for ordinary rice, i.e., 42.04 ± 20.65 [mmol/(L·min)] vs. 45.53 ± 22.45 [mmol/(L·min)] (P = 0.043), 143.54 ±69.63 [mmol/(L·min)] vs. 155.15 ± 73.53 [mmol/(L·min)] (P = 0.026), and 354.61 ± 191.96 [mmol/(L·min)] vs. 379.78 ± 195.30 [mmol/(L·min)] (P = 0.042) at 30, 60, and 120 min, respectively. Repeated-measures ANOVA showed that postprandial glucose levels were not affected by the test order.

Conclusion

The novel high-RS rice as a staple food when substituting for widely consumed ordinary rice may provide potential health benefits by lowering blood glucose in patients with type 2 diabetes.

Resistant starch type-4 intake alters circulating bile acids in human subjects

BACKGROUND

Resistant starch (RS) type 4 (RS4) is a type of RS, a class of non-digestible prebiotic dietary fibers with a range of demonstrated metabolic health benefits to the host. On the other hand, bile acids (BA) have recently emerged as an important class of metabolic function mediators that involve host-microbiota interactions. RS consumption alters fecal and cecal BA in humans and rodents, respectively. The effect of RS intake on circulating BA concentrations remains unexplored in humans.

METHODS AND RESULTS

Using available plasma and stool samples from our previously reported double-blind, controlled, 2-arm crossover nutrition intervention trial (Clinicaltrials.gov: NCT01887964), a liquid-chromatography/mass-spectrometry-based targeted multiple reaction monitoring, and absolute quantifications, we assessed BA changes after 12 weeks of an average 12 g/day RS4-intake. Stool BA concentrations were lower post RS4 compared to the control, the two groups consuming similar macronutrients (n = 14/group). Partial least squares-discriminant analysis revealed distinct BA signatures in stool and plasma post interventions. The increased circulating BA concentrations were further investigated using linear mixed-effect modeling that controlled for potential confounders. A higher plasma abundance of several BA species post RS4 was observed (fold increase compared to control in parenthesis): taurocholic acid (1.92), taurodeoxycholic acid (1.60), glycochenodeoxycholic acid (1.58), glycodeoxycholic acid (1.79), and deoxycholic acid (1.77) (all, p < 0.05). Distinct microbiome ortholog-signatures were observed between RS4 and control groups (95% CI), derived using the Piphillin function-prediction algorithm and principal component analysis (PCA) of pre-existing 16S rRNA gene sequences. Association of Bifidobacterium adolescentis with secondary BA such as, deoxycholic acid (rho = 0.55, p = 0.05), glycodeoxycholic acid (rho = 0.65, p = 0.02), and taurodeoxycholic acid (rho = 0.56, p = 0.04) were observed in the RS4-group, but not in the control group (all, p > 0.05).

CONCLUSION

Our observations indicate a previously unknown in humans- RS4-associated systemic alteration of microbiota-derived secondary BA. Follow-up investigations of BA biosynthesis in the context of RS4 may provide molecular targets to understand and manipulate microbiome-host interactions.

Pea-Resistant Starch with Different Multi-scale Structural Features Attenuates the Obesity-Related Physiological Changes in High-Fat Diet Mice

The present study compared the modulatory effects of different resistant starches (RSs) isolated from native (NP-RS), acid-hydrolyzed (AHP-RS), and pullulanase debranched (PDP-RS) pea starches on the corresponding in vivo metabolic responses in high fat (HF)-diet-induced obese mice. The biochemical studies on serum lipid profile and antioxidant enzyme activities were supported by histological and gene expression analyses, which suggested a potential therapeutic role for RS in regulating obesity, possibly through the production of short-chain fatty acids and the proliferation of some beneficial colonic bacteria, including Allobaculum, Bifidobacterium, Odoribacter, Clostridium, and Prevotella. Particularly, a more pronounced effect of AHP-RS with a higher proportion of the crystalline region and a more ordered double-helical alignment on improving the hyperlipidemic symptoms in obese mice induced by a HF diet was observed. Our analysis revealed that the RS3 samples seemed to be more effective than RS2 in terms of attenuating obesity in mice that were fed a HF diet.

In vitro digestion of a mixed gel of pork muscle and resistant starch: Salt-soluble protein perspective

The in vitro digestion of a mixed gel (MS) of pork muscle and resistant starch (RS) was investigated and the role of the salt-soluble protein (SSP) in the function promotion of the mixed gel was clarified. The results showed that the mixed muscle gel (MS) and the addition of RS to muscle gel (M + S) presented an improved protein digestion, as indicated by a reduced particle size of the hydrolysates, more degradation of proteins with large molecular weight and more generation of free amino acids compared with the RS-free muscle gel (M). Meanwhile, the hydrolysates of the M + S and MS showed intensified DPPH radical scavenging activities. Specifically, the MS exerted preferable properties in protein digestion and antioxidant activity. Similar digestion characteristics were noticed in mixed SSP gels.The current study revealed that the reinforced functionality of the mixed muscle gel was associated with the binding relationships between SSP and RS during cooking.

Amelioratory Effect of Resistant Starch on Non-alcoholic Fatty Liver Disease via the Gut-Liver Axis

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome with a global prevalence. Impaired gut barrier function caused by an unhealthy diet plays a key role in disrupting the immune-metabolic homeostasis of the gut-liver axis (GLA), leading to NAFLD. Therefore, dietary interventions have been studied as feasible alternative therapeutic approaches to ameliorate NAFLD. Resistant starches (RSs) are prebiotics that reduce systemic inflammation in patients with metabolic syndrome. The present review aimed to elucidate the mechanisms of the GLA in alleviating NAFLD and provide insights into how dietary RSs counteract diet-induced inflammation in the GLA. Emerging evidence suggests that RS intake alters gut microbiota structure, enhances mucosal immune tolerance, and promotes the production of microbial metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids. These metabolites directly stimulate the growth of intestinal epithelial cells and elicit GPR41/GPR43, FXR, and TGR5 signaling cascades to sustain immune-metabolic homeostasis in the GLA. The literature also revealed the dietary-immune-metabolic interplay by which RSs exert their regulatory effect on the immune-metabolic crosstalk of the GLA and the related molecular basis, suggesting that dietary intervention with RSs may be a promising alternative therapeutic strategy against diet-induced dysfunction of the GLA and, ultimately, the risk of developing NAFLD.

Anti-hyperlipidemic and ameliorative effects of chickpea starch and resistant starch in mice with high fat diet induced obesity are associated with their multi-scale structural characteristics

Chickpea starches were isolated from both untreated (UC-S) and conventionally cooked seeds (CC-S), and their multi-scale structural characteristics and in vivo physiological effects on controlling hyperlipidemia in high fat diet induced obese mice were compared with their corresponding resistant starch (RS) fractions obtained by an in vitro enzymatic isolation method (UC-RS and CC-RS). The degree of order/degree of double helix in Fourier transform infrared spectroscopy was in the following order: CC-RS > UC-RS > CC-S > UC-S, which was consistent with the trend observed for relative crystallinity and double helix contents monitored by X-ray diffractometer and solid-state ¹³C cross-polarization and magic angle spinning NMR analyses. The influence of different types of chickpea starch and their corresponding resistant starch fractions on regulating the serum lipid profile, antioxidant status, and histopathological changes in liver, colon and cecal tissues, and gene expressions associated with lipid metabolism, gut microbiota, as well as short-chain fatty acid metabolites in mice with high fat diet induced obesity was investigated. The results showed that the chickpea RS diet group exhibited overall better anti-hyperlipidemic and ameliorative effects than those of the starch group, and such effects were most pronounced in the CC-RS intervention group. After a six-week period of administration with chickpea starch and RS diets, mice in the UC-RS and CC-RS groups tended to have relatively significantly higher levels (P < 0.05) of butyric acid in their fecal contents. The 16S rRNA sequencing results revealed that mice fed with CC-RS showed the greatest abundance of Akkermansia and Lactobacillus compared with the other groups.

Acid-treated high-amylose corn starch suppresses high-fat diet-induced steatosis

Resistant starch (RS) has been reported to improve steatosis as well as obesity. Type 4 resistant starch (RS4), a chemically modified starch, is particularly hard to digest and suggesting higher efficacy. However, because the effects of RS4 on steatosis are not yet fully understood, the effects of RS4 on steatosis were examined using a murine high-fat diet model. Seven-week-old male mice were divided into three groups and fed a normal diet, a high-fat diet (HFD), or a high-fat diet with added RS (HFD + RS). Amylofiber SH^® produced from acid-treated corn starch was used as the dietary RS. At 22 weeks old, hepatic steatosis and short chain fatty acid (SCFA) content and gut microbiota in cecum stool samples were analyzed. The ratio of body weight to 7 weeks was significantly suppressed in the HFD + RS group compared to the HFD group (132.2 ± 1.4% vs. 167.2 ± 3.9%, p = 0.0076). Macroscopic and microscopic steatosis was also suppressed in the HFD + RS group. Analysis of cecum stool samples revealed elevated SCFA levels in the HFD + RS group compared with the HFD group. Metagenome analysis revealed that Bifidobacterium (17.9 ± 1.9% vs. 3.6 ± 0.7%, p = 0.0019) and Lactobacillus (14.8 ± 3.4% vs. 0.72 ± 0.23%, p = 0.0045), which degrade RS to SCFA, were more prevalent in the HFD + RS group than the HFD group. In conclusion, RS4 suppressed steatosis, and increased Bifidobacterium and Lactobacillus, and SCFAs. RS4 may prevent steatosis by modulating the intestinal environment.

Betaine Supplementation Causes an Increase in Fatty Acid Oxidation and Carbohydrate Metabolism in Livers of Mice Fed a High-Fat Diet: A Proteomic Analysis

Betaine, a common methyl donor whose methylation is involved in the biosynthesis of carnitine and phospholipids in animals, serves as food and animal feed additive. The present study used liquid chromatography-mass spectrometry (LC-MS) to analyze the liver protein profile of mice on a high fat (HF) diet to investigate the mechanism by which betaine affects hepatic metabolism. Although betaine supplementation had no significant effect on body weight, a total of 103 differentially expressed proteins were identified between HF diet + 1% betaine group (HFB) and HF diet group by LC-MS (fold change > 2, p < 0.05). The addition of 1% betaine had a significant enhancement of the expression of enzymes related to fatty acid oxidation metabolism, such as hydroxyacyl-Coenzyme A dehydrogenase (HADHA), enoyl Coenzyme A hydratase 1 (ECHS1) (p < 0.05) etc., and the expression of apolipoprotein A-II (APOA2) protein was significantly reduced (p < 0.01). Meanwhile, the protein expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and succinate-CoA ligase (SUCLG1) were highly significant (p < 0.01). Pathway enrichment using the Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that the functions of differential proteins involved fatty acid catabolism, carbohydrate metabolism, tricarboxylic acid cycle (TCA) and peroxisome proliferator-activated receptor alpha (PPARα) signaling pathway. Protein−protein interaction (PPI) analysis discovered that acetyl-Coenzyme A acetyltransferase 1 (ACAT1), HADHA and ECHS1 were central hubs of hepatic proteomic changes in the HFB group of mice. Betaine alleviates hepatic lipid accumulation by enhancing fatty acid oxidation and accelerating the TCA cycle and glycolytic process in the liver of mice on an HF diet.

Dietary fibers with different viscosity regulate lipid metabolism via ampk pathway: roles of gut microbiota and short-chain fatty acid

Dietary fiber (DF) improves gastrointestinal health and has important associations with the alleviation of intestinal diseases and metabolic syndrome. However, due to DFs complex characteristics, such as solubility, viscosity, and fermentability, the mechanism in these was not consistent. As an herbivore, the goose has a prominent digestive ability to DF.

Therefore, we choose low, medium, and high viscosity DFs (respectively resistant starch-3 []RS], inulin [INU], and β–glucan [GLU]) as Magang goose diet treatment for 4 wk, to investigate the effect and potential mechanism of different viscosities DFs on the growth and development process of goose.

In summary, three degrees of viscous DFs could decrease the mechanismic lipid level of geese by promoting acid-producing bacteria and short-chain fatty acid (SCFA) production, therefore, activating AMPK pathway-related genes through the gut-liver axis. High viscous DF has a greater lipid-lowering effect on geese, while medium viscous DF has preferable intestinal mucosal protection.

Biotic Supplements in Patients With Chronic Kidney Disease: Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Gut flora imbalance characterizes patients with chronic kidney disease (CKD). Although biotic supplementation has been proposed to lessen inflammation and oxidative stress and, thus, reduce the risk of progressive kidney damage and cardiovascular disease, the effects remain controversial. We conducted a meta-analysis to assess the therapeutic benefits of biotics in CKD.

METHODS

PubMed, Embase, and Cochrane databases were systematically searched for randomized controlled trials that evaluated any biotic (prebiotic, probiotic, synbiotics) supplements in patients with CKD (CKD, stage 3-4 to end-stage renal disease). Primary endpoints included changes in renal function, markers of inflammation, and oxidative stress. Secondary endpoints included changes in levels of uremic toxins and variations in lipid metabolism.

RESULTS

Twenty-three eligible studies included 842 participants. In a pooled-analysis, biotics did not change estimated glomerular filtration rate (mean difference [MD] = 0.08, P = .92) or serum albumin (MD = -0.01, P = .86), although prebiotics reduced serum creatinine (standardized mean difference [SMD] = -0.23, P = .009) and blood urea nitrogen (MD = -6.05, P < .00001). Biotics improved total antioxidative capacity (SMD = 0.37, P = .007) and malondialdehyde (SMD = -0.96, P = .006) and reduced the inflammatory marker interleukin-6 (SMD = -0.30, P = .01) although not C-reactive protein (SMD = -0.22, P = .20). Biotic intervention reduced some uremic toxins, including p-cresol sulfate (SMD = -2.18, P < .0001) and indoxyl sulfate (MD = -5.14, P = .0009), which decreased in dialysis-dependent patients. Another toxin, indole-3-acetic acid (MD = -0.22, P = .63), did not change. Lipids were unaffected by biotic intervention (total cholesterol: SMD = -0.01, P = .89; high-density lipoprotein: SMD = -0.08, P = .76; low-density lipoprotein: MD = 3.54, P = .28; triglyceride: MD = -2.26, P = .58).

CONCLUSION

The results highlight the favorable influence of biotics on circulating markers of creatinine, oxidant stress (malondialdehyde, total antioxidative capacity), inflammation (interleukin-6), and uremic toxins (p-cresol sulfate) in patients with CKD. Biotics did not affect estimated glomerular filtration rate, albumin, indole-3-acetic acid, or lipids in either predialysis or dialysis patients.

Manipulations of glucose/lipid metabolism and gut microbiota of resistant starch encapsulated Ganoderma lucidum spores in T2DM rats

Our team previously demonstrated that Ganoderma lucidum spores (GLS) and resistant starch (RS) had hypoglycemic effects separately on type 2 diabetic mellitus (T2DM) rats. This work was to explore the effects of administering encapsulated GLS within RS (referred to as EGLS) in the T2DM rats, which were induced by streptozotocin (STZ). The EGLS was orally administered to rats for 28 days. The parameters of glycometabolism and lipometabolism were evaluated, and fecal microbiota composition was investigated. The results showed that EGLS significantly enhanced glycometabolism and lipometabolism parameters in T2DM rats, which might be associate with the enhancement of the glucose and lipid metabolism, insulin secretion, and glycogen synthesis and reduced lipogenesis. Furthermore, the intervention of EGLS also reduced the Proteobacteria community and improved dysfunctional gut microbiota. This study indicated EGLS may be a potential candidate for dietary intervention to modulate diabetes.

Effects of proteins on the structure, physicochemical properties, and in vitro digestibility of wheat starch-lauric acid complexes under various cooking methods

Herein, we investigated the effects of gluten proteins (Pr) on the structure, physicochemical properties, and in vitro digestibility of wheat starch-lauric acid (WS-LA) complexes under various cooking methods (steaming, boiling, and baking). There was no ternary complex formation between WS, LA, and Pr in the samples after different cooking methods. Scanning electron microscopy (SEM) and fluorescence microscopy showed variation in size, structure and distribution of WS-LA of WS-LA-Pr samples after cooking. An increase in the intensity of V-type diffraction peak and thermal stability was observed in steamed and baked samples, however, opposite trend was noticed in boiled sample. Additionally, a higher 1022/995 cm^-1 absorbance ratio was noted in WS-LA-Pr sample treated with boiling than other cooking methods. Further, in vitro resistance to enzymatic hydrolysis was improved in samples treated with steaming and baking compared with boiled treated samples. In sum, this study may offer a thorough understanding on how these interactions take place during food processing, to optimize the production and development of new food products with desired microstructure and functionality features.

The anti-obesity effects exerted by different fractions of Artemisia sphaerocephala Krasch polysaccharide in diet-induced obese mice

Artemisia sphaerocephala Krasch polysaccharide (ASKP) consists of two main fractions, 60P (molecular weight at 551 kDa) and 60S (molecular weight at 39 kDa). The anti-obesity effects of ASKP and its two fractions were investigated in high-fat-diet-fed mice and showed similar capability in efficiently preventing the development of obesity. The final body weight and body weight gain of obesity mice model were reduced by 12.44% and 35.33% by ASKP, 10.63% and 34.35% by 60P, and 7.82% and 20.04% by 60S. They also showed similar efficiency to ameliorate dyslipidemia, systematic inflammation, and gut dysbiosis. The colonic genes of barrier integrity were significantly upregulated and the genes of hepatic lipid metabolism and that of colonic inflammatory response were suppressed. They attenuated the gut dysbiosis in obese mice, such as the significant enrichment of beneficial genera (Bifidobacterium and Olsenella) and suppression of harmful ones (Mucispirillum and Helicobacter). Significant enrichment of carbohydrate metabolism associated with the promotion of short-chain fatty acid production and decrease of the metabolisms related to obesity and gut dysbiosis (valine, leucine, and isoleucine biosynthesis, and nitrogen metabolism) were also observed by the administration of ASKP, 60P, and 60S. Overall, these polysaccharides showed potential in acting as prebiotics in preventing high-fat-diet-induced obesity.

Functional hydrocolloids, gut microbiota and health: picking food additives for personalized nutrition

The human gut microbiota respond to particular food components, interact with intestinal mucosa and thereby contribute to health and diseases. Key microbiome features are under comprehensive investigation and are likely to be developed as reliable evidences for clinical diagnosis. And the underlying mechanisms lay the foundation of assembling bespoke nutritional ingredients including functional food additives that may lead to favorable outcomes in facilitating amelioration of host dysfunctions. Functional hydrocolloids serve as multiple food additives with promising application prospects and outstanding adjunctive beneficial characteristics. Therefore, in this review, we introduce the latest advances in food additives-gut microbiota-host axis by summarizing the physiochemical and physiological properties of a collection of functional hydrocolloids from various sources, describing the functional hydrocolloids-related intestinal commensal markers, and deciphering the underlying mechanisms of their beneficial effects, and propose the feasibilities and guidelines for further developments of gut microbiota-oriented personalized nutrition.

Glucose and lipid metabolism of broiler chickens fed diets with graded levels of corn resistant starch

1. The aim of this study was to investigate the effects of graded levels of dietary corn resistant starch (RS) on glucose and lipid metabolism of broilers. 2. A total of 320 male broiler chicks (Arbor Acres, one-day-old) were randomly allocated to five dietary treatments, including a corn-soybean control diet, a corn-soybean based diet containing 20% corn starch, and three diets containing 4%, 8% and 12% RS by replacing corn starch with 6.67%, 13.33% and 20% Hi-Maize® 260 (identified as control, RS1, RS2, RS3 and RS4, respectively). Each treatment contained eight replicates with eight birds, and the experiment lasted 42 days. 3. Birds fed RS diets showed lower (P < 0.05) concentrations of serum low-density lipoprotein cholesterol and non-esterified fatty acid (NEFA) at d 21 and 42 of age, compared to the control. Lower (P < 0.05) hepatic apolipoprotein B concentration and citrate synthase (CS) activity, as well as a higher (P < 0.05) glycogen synthase (GS) concentration were observed in birds fed RS diets than those in the control group at d 21 of age. Consuming RS diets linearly increased (P < 0.01) serum glucose concentration, and linearly decreased (P < 0.01) NEFA concentrations in broilers at d 21 and 42 of age. Liver GS concentration and activities of hexokinase, pyruvate and CS were linearly increased (P < 0.01) in broilers at d 21 of age, but were linearly decreased (P < 0.05) in birds at d 42 of age in response to the increase of dietary RS levels. Feeding RS diets linearly decreased (P < 0.05) mRNA expressions of PC, PPARα and CPT-1 at d 21 of age and the mRNA expressions of SREBP-1 c, ChREBP, ACC and FAS at d 42 of age, and linearly increased (P < 0.05) the mRNA expressions of PEPCK, PC, LKB1, AMPKα1, PPARα, CPT-1 and L-FABP at d 42 of age. 4. Feeding broilers with diets containing higher concentration of RS promoted hepatic lipolysis and gluconeogenesis through activated AMPK signalling pathway and accelerated whole-body energy expenditures in the grower phase.

A more pronounced effect of type III resistant starch vs. type II resistant starch on ameliorating hyperlipidemia in high fat diet-fed mice is associated with its supramolecular structural characteristics

The anti-obesity effects of two categories of resistant starch (RS) including RS₂ (isolated from untreated lentil starch, URS) and RS₃ (isolated from autoclaved and retrograded lentil starch, ARS) on mice with high-fat (HF) diet-induced obesity and the supramolecular structure-in vivo physiological functionality relationship of RS were investigated. Following 6 consecutive weeks, the obese mice in the two RS administered groups displayed suppression of body/liver weight gain and an improvement in serum glucose/lipid profile, antioxidant status, and gut microbiota structure. Compared with the URS intervention group, the ARS administration resulted in a more pronounced effect in controlling body weight, together with a more prominent reduction in blood glucose and triglyceride concentration, as well as a significant increase in the HDL-c level in obese mice. The ARS group also showed an absolute advantage over URS in suppressing the oxidative stress and regulating the liver function induced by the HF diet. Simultaneously, the administration of URS and ARS efficiently suppressed the HF-diet induced alterations in gut microbial ecology, with an obviously decreased ratio of Firmicutes to Bacteroidetes, especially for the ARS group, suggesting its beneficial role in gastrointestinal tract health. The structural characterization results revealed that ARS and URS differed significantly in their supramolecular structural characteristics, where ARS exhibited a higher proportion of crystallinity and double helix content with an X-ray diffraction pattern of a C_B type crystal polymorph and a low proportion of molecular inhomogeneity. This study suggested that the difference in the anti-obesity effect of resistant starches was a consequence of the diversity in their structural features.

Resistant starch supplementation attenuates inflammation in hemodialysis patients: a pilot study

PURPOSE

In chronic kidney disease (CKD) patients, dysbiosis is associated with inflammation and cardiovascular risk, so many nutritional strategies are being studied to reduce these complications. Resistant starch (RS) can be considered a prebiotic that promotes many benefits, including modulation of gut microbiota which is linked to immune-modulatory effects. The aim of this study was to evaluate the effects of RS supplementation on proinflammatory cytokines in CKD patients on hemodialysis (HD).

METHODS

A double-blind, placebo-controlled, randomized trial was conducted with sixteen HD patients (55.3 ± 10.05 years, body mass index (BMI) 25.9 ± 5.42 kg/m², 56% men, time on dialysis 38.9 ± 29.23 months). They were allocated to the RS group (16 g RS/day) or placebo group (manioc flour). The serum concentration of ten cytokines and growth factors was detected through a multiparametric immunoassay based on XMap-labeled magnetic microbeads (Luminex Corp, USA) before and after 4 weeks with RS supplementation.

RESULTS

After RS supplementation, there was a reduction of Regulated upon Activation, Normal T-Cell Expressed and Secreted (p < 0.001), platelet-derived growth factor (two B subunits) (p = 0.014) and interferon-inducible protein 10 (IP-10) (p = 0.027). The other parameters did not change significantly.

CONCLUSION

This preliminary result indicates that RS may contribute to a desirable profile of inflammatory markers in CKD patients.

Could resistant starch supplementation improve inflammatory and oxidative stress biomarkers and uremic toxins levels in hemodialysis patients? A pilot randomized controlled trial

An imbalance of gut microbiota is considered a new cardiovascular risk factor for chronic kidney disease (CKD) patients, since it is directly associated with increased uremic toxin production, inflammation and oxidative stress. Strategies such as prebiotic supplementation have been suggested to mitigate these complications. We hypothesized that prebiotic-resistant starch could ameliorate uremic toxins levels, oxidative stress, and inflammatory states in hemodialysis (HD) patients. This pilot study evaluated 31 HD patients assigned to either resistant starch (16 g of resistant starch Hi-Maize® 260) or placebo (manioc flour) supplementation, which they received for 4 weeks on alternate days through cookies on dialysis days and powder in a sachet on non-dialysis days. Levels of interleukin (IL)-6, high-sensitive C-reactive protein, thiobarbituric acid reactive substances plasma (TBARS), protein carbonylation, indoxyl sulfate (IS) and p-cresyl sulfate were measured. Anthropometric and biochemical parameters, as well as, food intake were also evaluated. As expected, resistant starch group increased fiber intake (p > 0.01), in addition the prebiotic supplementation reduced IL-6 (p = 0.01), TBARS (p > 0.01), and IS (p > 0.01) plasma levels. No significant differences were evident in the placebo group. Prebiotic-resistant starch supplementation seems to be a promising nutritional strategy to improve inflammation, oxidative stress and to reduce IS plasma levels in CKD patients on HD.

Attenuation of metabolic syndrome in the ob/ob mouse model by resistant starch intervention is dose dependent

The effect of different RS concentrations on the morphology of colon (A), liver (B) and adipose tissue (C).

The beneficial effects of purple yam (Dioscorea alata L.) resistant starch on hyperlipidemia in high-fat-fed hamsters

In this study, we investigated the interventional effect of resistant starch (RS) obtained from purple yam (Dioscorea alata L.) on regulating lipid metabolism and gut microbiota in hyperlipidemic hamsters.

Improvement in Nutritional Attributes of Rice Starch with Dodecyl Gallate Complexation: A Molecular Dynamic Simulation and in Vitro Study

To improve starch functionalities such as digestibility and antioxidant activity, rice starch was complexed with antioxidant dodecyl gallate (DG). Molecular dynamics simulation showed that the starch-DG inclusion complex was favorable, and in 50 ns, the dodecyl segment resided in the helix of the amylose cavities but the gallate tail left outside. This theoretical finding was validated by UV-vis spectroscopy, calorimetric, and crystalline measurements, indicating V-type crystalline structures containing type I and type II inclusion complexes can be formed after DG complexation. Meritedly, starch digestibility was mitigated by synchronously increasing slowly digestible starch (5.12-22.83%) and resistant starch content (8.69-14.17%), and the antioxidant activity was also significantly increased. Such inclusion complexes thereby acted as a carrier for targeting delivery of DG to the human lower gastrointestinal tract with potent antioxidant activity. Complexation with DG synergistically improved starch digestibility and antioxidant activity, favoring the intervention against chronic diseases, by ameliorating the postprandial glycemic response and oxidative stress.

Gut Microbiome-Induced Shift of Acetate to Butyrate Positively Manages Dysbiosis in High Fat Diet

SCOPE

A recent study revealed that the accumulation of gut microbiota-produced acetate (GMPA) led to insulin over-secretion and obesity symptom. To further develop this scientific point, the effect of resistant starch (RS) or exogenous acetate carried by RS (RSA) in the gut on metabolic syndrome is investigated using diet-induced obese rats.

METHODS AND RESULTS

The metabonomics analysis shows that the gut of rats in the RSA group generate more butyrate in both serum and feces rather than acetate compared to the rats in RS group, indicating the conversion among metabolites, in particular from acetate to butyrate via gut microbiota. Consistently, the gut microbiome uses acetate as a substrate to produce butyrate, such as Coprococcus, Faecalibacterium, Roseburia, and Eubacterium and was highly promoted in RSA group, which further supports the metabolic conversion. This is the first report to reveal the accumulation of gut microbiota-produced butyrate (GMPB) but not GMPA significantly enriched AMPK signaling pathway with reduced expression of lipogenesis-associated genes for suppressing sphingosines and ceramides biosynthesis to trigger insulin sensitivity.

CONCLUSION

Gut microbiome profile and lipogenesis pathway are regulated by GMPB, which substantially influences energy harvesting in the gut from patterns opposed to GMPA.

Association of changes in ER stress-mediated signaling pathway with lead-induced insulin resistance and apoptosis in rats and their prevention by A-type dimeric epigallocatechin-3-gallate

A-type dimeric epigallocatechin-3-gallate (A-type-EGCG-dimer, AEd), a new proanthocyanidins dimer from persimmon fruits, has been shown to have health benefit effects. However, A-type-EGCG-dimer affects gluose metabolism in the liver and the underlying mechanism is not clarified. The present study aims to examine the protective effects of A-type-EGCG-dimer on Pb-induced hepatic insulin resistance, endoplasmic reticulum (ER) stress and apoptosis in rats. Male wistar rats exposed to 0.05% w/v Pb acetate in the drinking water with or without A-type-EGCG-dimer coadministration (200 mg/kg body weight/day, intragastrically) for three months. We found that A-type-EGCG-dimer and pioglitazone supplementation significantly deceased glucose and insulin levels in plasma as compared with the Pb group. A-type-EGCG-dimer markedly prevents Pb-induced oxidative stress, ER stress and apoptosis in livers. A-type-EGCG-dimer and pioglitazone reduced the expression levels of the GRP78, PEPCK, G6Pase, p-PERK, p-IRE1, p-JNK, ATF4, CHOP and increased p-AKT in livers of the Pb group. Moreover, A-type-EGCG-dimer reduced ROS production and restored the activities of SOD and GPx in livers. A-type-EGCG-dimer decreased Bax, cytosolic cytochrome c and cleaved caspase-3 and increased Bcl-2 in livers of Pb-exposed rats. Our results suggest that A-type-EGCG-dimer might be a potential natural candidate for the prevention of hepatic insulin resistance and apoptosis induced by Pb.

Flavonoid-Rich Extract of Paulownia fortunei Flowers Attenuates Diet-Induced Hyperlipidemia, Hepatic Steatosis and Insulin Resistance in Obesity Mice by AMPK Pathway

The flavonoid-rich extract from Paulownia fortunei flowers (EPF) has been reported to prevent obesity and other lipid metabolism disease. However, the mechanism of its protective effects is not yet clear. The objective of this study was to investigate molecular factors involved in the hypoglycemic and hypolipidemic effects of EPF in obese mice fed a high-fat diet (HFD). Male h ICR (Institute of Cancer Research) mice were fed a HFD containing or not containing the EPF (50 or 100 mg/kg) for eight weeks. EPF reduced body weight gain, lipid accumulation in livers and levels of lipid, glucose and insulin in plasma as well as reduced insulin resistance as compared with the HFD group. EPF significantly decreased serum aminotransferase activity of the HFD group. We observed that EPF administration significantly increased the level of AMP-activated kinase (AMPK) phosphorylation and prevented fat deposits in livers and HepG2 cells, but these effects were blocked by compound C (an AMPK inhibitor). The protective effects of EPF were probably associated with the decrease in HMGCR, SREBP-1c and FAS expressions and the increase in CPT1 and phosphor-IRS-1 expressions. Our results suggest that EPF might be a potential natural candidate for the treatment and/or prevention of overweight and hepatic and metabolic-related alterations induced by HFD.

Resistant starch attenuates impaired lipid biosynthesis induced by dietary oxidized oil via activation of insulin signaling pathways

The current study found that deep-frying process led to an increased content of oxidized triacylglycerols in canola oil, 3.5 times higher than that of fresh canola oil (not used for frying).