Drought Induces Distinct Growth Response, Protection, and Recovery Mechanisms in the Maize Leaf Growth Zone

Drought is the most important crop yield-limiting factor, and detailed knowledge of its impact on plant growth regulation is crucial. The maize (Zea mays) leaf growth zone offers unique possibilities for studying the spatiotemporal regulation of developmental processes by transcriptional analyses and methods that require more material, such as metabolite and enzyme activity measurements. By means of a kinematic analysis, we show that drought inhibits maize leaf growth by inhibiting cell division in the meristem and cell expansion in the elongation zone. Through a microarray study, we observed the down-regulation of 32 of the 54 cell cycle genes, providing a basis for the inhibited cell division. We also found evidence for an up-regulation of the photosynthetic machinery and the antioxidant and redox systems. This was confirmed by increased chlorophyll content in mature cells and increased activity of antioxidant enzymes and metabolite levels across the growth zone, respectively. We demonstrate the functional significance of the identified transcriptional reprogramming by showing that increasing the antioxidant capacity in the proliferation zone, by overexpression of the Arabidopsis (Arabidopsis thaliana) iron-superoxide dismutase gene, increases leaf growth rate by stimulating cell division. We also show that the increased photosynthetic capacity leads to enhanced photosynthesis upon rewatering, facilitating the often-observed growth compensation.

Anthocyanins in Strawberry Polyphenolic Extract Enhance the Beneficial Effects of Diets with Fructooligosaccharides in the Rat Cecal Environment

The administration of fructooligosaccharides (FOS) beneficially modulates gastrointestinal functions and may enhance the metabolism of polyphenols. However, different polyphenolic components in the diet may have different influences on the activities of the digestive enzymes and microbiota in the gastrointestinal tract. Therefore, a 4-week study of forty-eight male Wistar rats was conducted to investigate the physiological response of the rat cecal environment to diets without and with FOS that contained two different strawberry polyphenolic extracts, specifically EP (polyphenolic profile 60, 35, 5, and 0% ellagitannins, proanthocyanidins, flavonols, anthocyanins, respectively) and EPA (polyphenolic profile: 50, 35, 6, and 9%, respectively). When combined with FOS, both extracts beneficially enhanced the acidification of the cecal digesta (P≤0.05 vs the groups without extracts), but the dietary combination of EPA and FOS elicited the greatest reduction in putrefactive short-chain fatty acid production and the lowest fecal β-glucuronidase activity in the cecum (P≤0.05 vs group EP). Moreover, the addition of dietary FOS elevated the metabolism of the examined strawberry extracts in the cecum and thereby increased the concentrations of the metabolites in the cecal digesta and urine (P≤0.05 vs the group with cellulose). Overall, both strawberry extracts modulated the effects of FOS in the gastrointestinal tract; however, the combination with EPA extract that contained anthocyanins exhibited greater beneficial effects in the lower gut environment than the EP extract.

Strawberry ellagitannins thwarted the positive effects of dietary fructooligosaccharides in rat cecum

Forty-eight male Wistar rats were fed diets containing low (0.051% of diet) or high (0.153% of diet) levels of an ellagitannin-rich (ET) strawberry extract with dietary fructooligosaccharides (FOS) or cellulose (CEL) for 4 weeks. The in vivo study demonstrated that some positive changes in the cecal metabolism resulting from the ingestion of a diet enriched only with FOS were completely or slightly suppressed by the dietary ET. In particular, the pH value (7.21 vs 7.36), short-chain fatty acid production (41.2 vs 30.0 μmol/100g BW), and β-glucuronidase activity (20.2 vs 15.7 μmol/h/g) in the cecum of rats fed with FOS were affected upon the addition of the ET extract. Dietary FOS caused higher metabolism of the tested ET strawberry extract in the gastrointestinal tract of rats. Moreover, the systemic effect of the supplements when consumed together showed undesired serum HDL-cholesterol decrease (0.78 vs 1.02 mmol/L in the treatment with FOS only).

Metabolism of strawberry mono- and dimeric ellagitannins in rats fed a diet containing fructo-oligosaccharides

PURPOSE

We investigated the effects of dietary supplementation with strawberry extracts rich in ETs and fructo-oligosaccharides (FOS) on the intestinal microbiota and the formation of bacterial metabolites in the distal intestine, as well as the absorption of ET metabolites and antioxidant status in rats.

METHODS

Rats were allocated into six groups of eight animals each and fed for 4 weeks with a control diet (group C), a control diet supplemented with FOS (group C + FOS) or modifications of these diets, in which a monomeric or dimeric ET-rich extract was added (groups ME and ME + FOS or DE and DE + FOS, respectively).

RESULTS

The extract addition, the FOS addition and their interaction significantly affected the total and selected bacterial counts in the caecal digesta (all P < 0.005). The total bacterial count was the highest in group C + FOS, lower in group DE and the lowest in group ME + FOS (10.6, 10.3 and 8.52 log cells/g, respectively; P ≤ 0.05). The total caecal content of ET metabolites was higher in the ME and ME + FOS group than in the DE and DE + FOS group, respectively (67.8 and 89.5 vs. 13.0 and 18.0 µg/g, respectively; P < 0.001). The total plasma concentration of ET metabolites was higher in the ME + FOS and DE + FOS group than in the ME group (248 and 281 vs. 8.13 ng/mL, respectively; P < 0.001).

CONCLUSIONS

ETs of the monomeric ET-rich extract are more prone to intestinal breakdown than those of the dimeric ET-rich extract, and absorption of their metabolites can be increased by dietary FOS; however, together, they evoke strong antibacterial activity.

Cannabis-derived cannabidiol and nanoselenium improve gut barrier function and affect bacterial enzyme activity in chickens subjected to C. perfringens challenge

Revealing the multifocal mechanisms affecting cross-talk between Clostridium perfringens pathogenesis and the host response is an urgent need in the poultry industry. Herein, the activity of Cannabis sativa-derived cannabidiol (CBD) and selenium nanoparticles (Nano-Se) in modulating the host response to Clostridium perfringens challenge was investigated in broiler chickens subjected to a mild infection model. The infected chickens exhibited no clinical manifestations, confirming the potential hazard of pathogen transmission to the food chain in the commercial sector. However, both CBD and Nano-Se affected the responses of chickens to C. perfringens challenge. The beneficial actions of both agents were manifested in the upregulated expression of genes determining gut barrier function. Both CBD and Nano-Se promoted shifts in gut bacterial enzyme activity to increased energy uptake in challenged chickens and upregulated potential collagenase activity. There was no opposite effect of CBD and Nano-Se in mediating the host response to challenge, whereas an additive effect was evidenced on the upregulation of gene determining gut integrity. Collectively, these findings indicate that understanding the action mechanisms of CBD and Nano-Se is of great interest for developing a preventive strategy for C. perfringens infection in broilers.

Protein-Rich Flours from Quinoa and Buckwheat Favourably Affect the Growth Parameters, Intestinal Microbial Activity and Plasma Lipid Profile of Rats

In recent years, dietary products with quinoa and buckwheat have attracted attention mostly due to the high nutritive value of their protein fraction. However, their dietary effect on intestinal microbiota activity and related systemic responses are still poorly understood. Therefore, a 2 week study of twenty-eight growing male Wistar rats was conducted to investigate the effects of quinoa (QU) and buckwheat (BK) protein-rich flours on the growth parameters, intestinal microbial activity, plasma lipid profile, and inflammatory markers. The biological value of protein and body weight gain were considerably increased in the QU and BK groups compared with those in the soy protein isolate group. Moreover, both flours increased the microbial activity of α-glucosidase, β-glucosidase, and α-galactosidase and the concentration of short-chain fatty acids in the caecum. The studied flours favourably reduced the plasma total cholesterol and LDL cholesterol. In rats fed a diet with QU, elevated levels of plasma interleukin 6 and alanine transaminase were observed. The effect of QU on inflammatory markers may be related to the increased expression of aryl hydrocarbon receptor in the liver and to the decreased level of plasma albumin. In conclusion, quinoa and buckwheat protein-rich flours are valuable sources of proteins that favourably affect growth parameters, gut metabolism, and blood lipid profile in rats; however, only the buckwheat flour has no effect on inflammatory processes.

Onion quercetin monoglycosides alter microbial activity and increase antioxidant capacity

The effects on fermentation processes in the digestive tract, the biochemical parameters and antioxidant capacity of blood in rats fed high-fat diets with quercetin (Q) and quercetin with quercetin monoglycosides (Q+MQ) preparations obtained from onion waste were evaluated. Four groups of eight animals were fed for 4 weeks with a control diet (C), a high-fat diet (HF) and high-fat diets with 0.15% addition of Q and Q+MQ preparations. HF caused an increase in alanine transaminase (ALT), non-high-density lipoprotein (non-HDL) and the atherogenic index AII vs. C and a decrease in the proportion of HDL in total cholesterol (TC). Q and Q+MQ showed a tendency to moderate the values aspartate transaminase (P=.087), ALT (P<.05), TC (P=.068), non-HDL cholesterol (P<.05), triglycerides (P=.064) and the atherogenic index AII (P<.05). Q+MQ significantly increased the activity of α-glucosidase (P<.05 vs. HF), β-glucosidase (P<.05) and β-galactosidase (P<.05 vs. C and Q). Q increased activity of β-glucosidase (P<.001 vs. C and HF). Both increased the activity of β-glucuronidase (P<.05 vs. C and HF). Both increased the antioxidant capacity of the hydrophilic fraction in serum (P<.05 vs. C and HF), and Q enhanced that of the lipid fraction (P<.001). Q preparation contained 70% quercetin, and Q+MQ preparation contained 29% quercetin and 13% quercetin monoglycosides, mainly quercetin-4'-glucoside. Both exhibited high antioxidant capacity. Supplementation with Q and Q+MQ increased the enzymatic activity of the intestinal microbiota and the antioxidant capacity of blood and revealed a tendency to improve the blood lipid profile. MQ were particularly effective in stimulating the bacterial enzymatic activity.

Raspberry pomace alters cecal microbial activity and reduces secondary bile acids in rats fed a high-fat diet

The profile of bile acids (BA) largely depends on the enzymatic activity of the microbiota, but this can be modulated by the dietary addition of biologically active compounds, e.g., polyphenols and polyunsaturated fatty acids. The aim of this study was to examine the effect of dietary raspberry pomace as a rich source of biologically active compounds on microbial activity and the BA profile in the caecum of rats fed a high-fat diet. Wistar rats were fed the standard diet AIN-93, a high-fat diet or a modified high-fat diet enriched with 7% different types of processed raspberry pomaces produced by standard grinding and fine grinding, with or without seeds. Rats fed the high-fat diet for 8 weeks showed some disorders in liver function and cecal BA, as manifested by an increased concentration of cholesterol, total BA in the liver and cholic, deoxycholic, and β-muricholic acids in the cecal digesta. In general, irrespective of the type of raspberry pomace, these dietary preparations decreased liver cholesterol, hepatic fibroblast growth factor receptor 4, peroxisome proliferator-activated receptor alpha, cecal ammonia and favorable changed BA profile in the cecum. However, among all dietary pomaces, the finely ground preparation containing seeds had the greatest beneficial effect on the caecum by modulating bacterial activity and reducing the levels of secondary BA.

Grinding levels of raspberry pomace affect intestinal microbial activity, lipid and glucose metabolism in Wistar rats

This study presents the effect of raspberry pomace and its grinding level on microbial activity in the gastrointestinal tract as well as on the parameters involved in the regulation of lipid and glucose metabolism in Wistar rats. The nutritional experiment was performed using 24 male Wistar rats, which were divided into 3 groups of 8 animals each. The animals were fed a standard diet (C) or a modified diet containing 7% raspberry pomace subjected to standard (SG) or fine (FG) grinding. Finer grinding increased the concentration of polyphenols and altered the composition of the dietary fibre, thereby affecting the intestinal microbial activity and related mechanisms that regulate systemic parameters. The FG diet considerably increased the level of total ellagitannin metabolites in the colon (23.56 μg/g for SG and 79.54 μg/g for FG) and plasma (0.029 μg/mL for SG and 0.041 μg/mL for FG) and reduced β-glucuronidase and α-glucosidase activity (19.2 and 19.7 for SG and 13.3 and 8.7 μmol/h/g for FG, respectively) and short-chain fatty acid production (55.84 μmol/g for SG and 48.60 μmol/g for FG) in the caecum. Compared to the SG, the FG diet improved the antioxidant capacity of water-soluble substances in plasma (4.34 μg/mL for SG and 4.92 μg/mL for FG). Both diets with raspberry pomaces increased the plasma HDL cholesterol (0.48 mmol/L for C, 0.56 mmol/L for SG, 0.57 mmol/L for FG) and decreased the atherogenic index (AI = (TC-HDL)/HDL: 2.57 for C, 1.98 for SG, 2.00 for FG). The FG diet resulted in the lowest plasma glucose level (10.8 mmol/L for C, 8.2 mmol/L for SG, 7.3 mmol/L for FG). In conclusion, both diets with raspberry pomaces modulated intestinal microbial activity and related systemic parameters; however, FG pomace exhibited greater inhibitory effects than SG pomace in the lower gut environment and glucose metabolism.

Dietary Supplementation with Raspberry Seed Oil Modulates Liver Functions, Inflammatory State, and Lipid Metabolism in Rats

BACKGROUND

Although raspberry seed oil (RO) is rich in essential fatty acids, there is a lack of experiments assessing benefits of its consumption.

OBJECTIVE

We investigated the effects of dietary supplementation with RO on healthy rats and rats with low-grade systemic inflammation, liver disorders, and dyslipidemia induced by a high-fat/low-fiber (HF/LF) diet.

METHODS

Thirty-two rats were allocated into 4 groups of 8 rats each and fed for 8 wk a control (C; 7% lard and 5% cellulose) or HF/LF (21% lard and 2% cellulose) diet or modifications of these diets in which 7% RO replaced all (C+RO group) or a proportion of (HF/LF+RO group) the lard. Effects of diet and RO and their interaction on bacterial activity and metabolite formations in the distal intestine, liver fat and glutathione concentration, plasma lipid profile, transaminase activities, and plasma concentrations of C-reactive protein (CRP) and tumor necrosis factor α (TNF-α) were tested.

RESULTS

Dietary RO decreased plasma alanine and aspartate transaminase activities (43.4 and 157 vs. 25.6 and 115 U/L, respectively; P < 0.05 and P < 0.005) and plasma TNF-α and triglyceride concentrations (132 pg/mL and 2.07 mmol/L vs. 86.5 pg/mL and 0.99 mmol/L, respectively; P < 0.05). In livers of the C+RO group, the fat concentration was decreased, whereas the glutathione to glutathione disulfide ratio was increased compared with the C group (30.1% and 6.20 μmol/g vs. 23.3% and 7.25 μmol/g, respectively; P ≤ 0.05); however, those differences were not observed between the HF/LF groups (P-interaction < 0.05). In the HF/LF+RO group, the plasma CRP concentration was lower than in the HF/LF group (88.1 vs. 765 pg/mL; P ≤ 0.05) and similar to that in the C and C+RO groups (158 and 128 pg/mL, respectively).

CONCLUSION

Dietary RO improves plasma lipid profile and liver functions and reduces low-grade systemic inflammation in rats; however, the extent of these beneficial effects is partly dependent on the diet type.

C. quinoa and S. hispanica L. Seeds Provide Immunonutritional Agonists to Selectively Polarize Macrophages

Diet-related immunometabolic-based diseases are associated with chronic inflammation in metabolic tissues, and infiltrated macrophages have been suggested as mediators for tissue- damaging inflammation. Growing evidence implicates Chenopodium quinoa and Salvia hispanica L. as important contributors to immunonutritional health. However, the functional roles of the immunonutritional protease inhibitors (PPIs) found in these crops on the macrophages' metabolic and phenotypic adaptation remain to be elucidated. The salt soluble fraction of proteins was extracted and analyzed confirming the presence of 11S and 2S albumin. The <30 kDa fraction of the extract from both crops was subjected to simulated gastrointestinal digestion, where (RP-LC-MS/MS analyses) polypeptides from 2S-type of proteins were found, along with the 2S albumin (13 kDa) for S. hispanica in the bioaccessible fraction (BAF). Using human-like macrophage cells to deepen our understanding of the modulatory effects of this BAF, FACS analyses revealed their potential as TLR4 agonists, favoring increased phenotypic CD68/CD206 ratios. The results of mitochondrial stress tests showed that cells increased oxygen consumption rates and non-mitochondrial respiration, confirming negligible deleterious effects on mitochondrial function. At molecular-level, adaptation responses shed light on changes showing biological correlation with TLR4 signaling. The resulting immunometabolic effects triggered by PPIs can be a part of a tailored nutritional intervention strategy in immunometabolic-based diseases.

Protocatechuic acid and quercetin glucosides in onions attenuate changes induced by high fat diet in rats

Yellow onion waste from industrial peeling was used to obtain three pure preparations: protocatechuic acid (PA), quercetin diglycosides (QD) and quercetin monoglycosides (QM). PA contained 61% protocatechuic acid, QD contained 35% quercetin diglucosides, mainly quercetin-3,4'-diglucoside, and QM contained 41% monoglucosides, mainly quercetin-4'-glucoside. The highest antioxidant activity was shown by PA. The effects of preparations on the digestive functions of the gastrointestinal tract of rats as well as the biochemical parameters and antioxidant capacity of the blood in model research on Wistar rats sustained by a high-fat diet were assessed (5 groups per 8 animals). The results of the present experiment showed that different onion phenolic preparations differently modulated the enzymatic activity of faecal (P < 0.001) and caecal (P < 0.001) microbiota. For instance, the QD preparation but not QM efficiently reduced the faecal and caecal bacterial β-glucuronidase activity. Both protocatechuic acid and quercetin monoglycosides showed a beneficial effect by regulating blood lipids (reduction of TC (P < 0.001) and TG (P < 0.001), non-HDL increase in HDL (P < 0.001)), thereby lowering the risk factors for atherosclerotic lesions AI (P = 0.038) and AII (P = 0.013). In addition, onion phenols showed a strong antioxidant effect, however, with a different mechanism: protocatechuic acid via serum ACL (P = 0.033) increase and hepatic GSSG (P = 0.070) decrease, QM via ACW (P < 0.001) increase and hepatic TBARS (P = 0.002) decrease, and QD via serum ACW increase and hepatic GSSG decrease. It can be concluded that onion polyphenols with a lower molar weight, i.e. QM more preferably affect the blood lipid profile than QD. However QD more efficiently reduced the faecal and caecal bacterial β-glucuronidase activity.

Protective Effects of Ellagitannin-Rich Strawberry Extracts on Biochemical and Metabolic Disturbances in Rats Fed a Diet High in Fructose

The present study compares the effects of two dietary strawberry extracts rich in monomeric (ME) or dimeric (DE) ellagitannins (ETs) on gastrointestinal, blood and tissue biomarkers in Wistar rats fed high-fructose diets. Both strawberry extracts beneficially affect the antioxidant status and lipid profile of the liver and serum. The ME extract shows a greater ability to inhibit lipid peroxidation in kidneys, more effectively decreases serum and liver triglycerides, and exerts greater anti-inflammatory effects in blood serum than the DE extract. The DE extract significantly reduces the activity of microbial enzymes in the cecum. These effects might be associated with higher cecum and urine levels of ET metabolites in rats fed with ME than in rats fed with DE. In conclusion, the diet-induced fructose-related disturbances observed in biochemical parameters are regulated by both extracts; nevertheless, the beneficial effects of the ME extract are mostly associated with systemic parameters, while those of the DE extracts are associated with local microbial activity.

Dietary Hemp Seeds More Effectively Attenuate Disorders in Genetically Obese Rats than Their Lipid Fraction

BACKGROUND

Hemp seeds are rich in PUFAs and other bioactives that can attenuate the development of obesity-related disorders; however, the extent to which their lipid fraction is responsible for this effect is unknown.

OBJECTIVE

We hypothesized that hemp seed or hemp oil supplementation can attenuate genetically determined disorders and that the former are more effective in doing so.

METHODS

Lean and obese male Zucker rats, aged 8 wk, weighing 174 ± 4.2 g and 223 ± 3.8 g, respectively, were allocated to 4 groups. The lean (LC) and obese controls (OC) were fed a standard diet, whereas the other 2 obese groups were fed a modified diet in which hemp oil (4% diet; O + HO) or hemp seeds (12% diet; O + HS) were included. All diets had the same proportions of protein (18%), fat (8%), and fiber (5%) and a similar carbohydrate proportion (∼52%). Diets fed to O + HO and O + HS had similar fatty acid profiles. After 4 wk, markers of gut and liver function, antioxidant status, and lipid metabolism were measured.

RESULTS

The total SCFA concentration in the cecal digesta was lower in OC (64.8 ± 4.21 µmol/g) compared with LC (78.1 ± 2.83 µmol/g) (P ≤ 0.05), whereas it was greater in O + HS (89 ± 4.41 µmol/g) compared with LC, OC, and O + HO (69.7 ± 2.68 µmol/g) (P ≤ 0.05). Plasma total cholesterol was greater in OC (6.20 ± 0.198 mmol/L) and O + HO (5.60 ± 0.084 mmol/L) compared with LC (2.71 ± 0.094 mmol/L) (P ≤ 0.05); in O + HS, the concentration did not differ from the other groups (5.16 ± 0.278 mmol/L). The liver cholesterol concentration was greater in OC (1.79 ± 0.379 mg/g) compared with the other groups (1.28-1.43 mg/g) (P ≤ 0.05). Hepatic expression of peroxisome proliferator-activated receptor γ was lower in OC (11.9 ± 0.93 units) compared with LC (17.3 ± 1.3 units) (P ≤ 0.05), whereas it was greater in O + HS (19.2 ± 1.04 units) compared with OC and O + HO (14.0 ± 1.33 units) (P ≤ 0.05).

CONCLUSIONS

Dietary hemp seeds more effectively attenuate metabolic disorders in genetically obese rats than the oil extracted from them, which suggests that the lipid fraction is only partly responsible for these effects.

Ellagitannins from Strawberries with Different Degrees of Polymerization Showed Different Metabolism through Gastrointestinal Tract of Rats

The present paper describes a comparative study of the metabolism of (1) ellagic acid, (2) monomeric ellagitannins (a mixture of α- and β-bis-hexahydroxydiphenoyl-d-glucose), and (3) dimeric ellagitannins (mainly agrimoniin with both glucose residues being esterified with hexahydroxydiphenoyl) in rats fed polyphenol-rich diets. Their metabolites were identified and quantified in selected parts of the gastrointestinal tract, i.e., the stomach, small intestine, and cecum, on the second, fourth, and seventh days of the experiment, as well as in the rats' feces, blood serum, and urine. Significant differences between the metabolites of strawberry ellagitannins and ellagic acid were observed in all parts of the gastrointestinal tract. Urolithin A was the predominant polyphenolic metabolite of rats fed a diet supplemented with ellagic acid. On the other hand, in rats fed low degree of polymerization (DP) ellagitannins, the main metabolite was nasutin followed by urolithin A, while ellagitannins with a higher DP led to nasutin only.

Effects of Different Chromium Compounds on Hematology and Inflammatory Cytokines in Rats Fed High-Fat Diet

The aim of the study was to determine how a high-fat diet supplemented with various forms of chromium affects hematological and immune parameters of the blood of rats. The rats received a standard diet or a high-fat diet supplemented with chromium at 0.3 mg/kg body weight (BW) in the form of chromium(III) picolinate, chromium(III)-methionine or nano-sized chromium. Selected hematological parameters were determined in the blood of the rats, including total white blood cell (WBC) count, leukogram, red blood cell (RBC) count, hemoglobin level (HGB), hematocrit (HCT), platelet count (PLT) and platelet percentage (PCT), as well as immune parameters: levels of immunoglobulins A and E (IgA and IgE), interleukin-6 (IL-6), interleukin-2 (IL-2), and tumor necrosis factor α (TNF-α); activity of ceruloplasmin (Cp); and levels of caspase 3 and 8 (Casp3 and Casp8). Feeding rats a high-fat diet increased blood markers of induction of inflammation, ie pro-inflammatory cytokines IL-6 and TNF-α, and also significantly increased IgE. The diet had no effect on the blood count, except for an increase in the number of neutrophils. The chromium compounds tested, particularly Cr-Met and Cr-NPs, stimulated the immune system of the rats, as indicated by increased concentrations of IgA, IgE, IL-2, IL-6, TNF-α, and Cp. Given the increase in inflammatory mediators induced by chromium, it should not be used to mitigate the effects of a high-fat diet. Moreover, chromium picolinate and chromium nanoparticles were shown to increase the content of caspase 3 and 8 in the blood of rats, which indicates a pro-apoptotic effect. The effects of the use of chromium nanoparticles include reductions in the WBC count and in the thrombocyte count (leuko- and thrombopenia). Taking account these data the use of chromium as dietary supplement should be reconsidered.

The Characterization of Ground Raspberry Seeds and the Physiological Response to Supplementation in Hypertensive and Normotensive Rats

This study aimed to evaluate the protective role of ground raspberry seeds (RBS) as a source of polyphenols and essential fatty acids on blood plasma enzymatic antioxidant status, lipid profile, and endothelium-intact vasodilation during physiological and pathological conditions. Young normotensive Wistar-Kyoto rats (WKYs) and spontaneously hypertensive rats (SHRs) at ten weeks of age were fed with either a control diet or were supplemented with added 7% RBS for six weeks (n = 6). The main component of RBS was dietary fiber (64%) and the main polyphenols were ellagitannins (1.2%) and flavan-3-ols (0.45%). Irrespective of the rat model, ground RBS decreased liver enzyme aspartate aminotransferase (0.9-fold) and hydrogen peroxide scavenging capacity (Catalase, 0.9-fold). In supplemented SHRs, preincubation with inducible nitric oxide synthase (iNOS) inhibitor 1400W, nonselective cyclooxygenase (COX) inhibitor indomethacin, selective COX-2 inhibitor NS-398, prostacyclin (PGI2) synthesis inhibitor tranylcypromine (TCP), thromboxane receptor (TP) antagonist SQ-29548, thromboxane synthesis inhibitor furegrelate, and 20-HETE synthesis inhibitor HET0016 induced the same relaxant response to acetylcholine as in the nonsupplemented control group. In supplemented WKYs, atherogenic index was decreased (0.8-fold), while iNOS and COX-2-derived PGI2 increased acetylcholine-induced vasodilation. These effects of ground RBS may constitute a potential mechanism for preventing cardiovascular diseases.

Dried fruit pomace inclusion in poultry diet: growth performance, intestinal morphology and physiology

Background

Fruit pomaces are by-products rich in polyphenol compounds and dietary fiber. They seem to play an important role in regulating the gut microbiota, morphology and physiology. The aim of this study was to assess whether apple (A), blackurrant (B) or strawberry (S) pomaces could be suitable ingredients in broiler diets and their effect on gut health. A total of 480 male broilers were randomly allotted to 8 dietary treatments with lower (3%-L) or higher (6%-H) dietary fiber content: two control groups (CL/CH), two A diets (AL/AH), two B diets (BL/BH), two S diets (SL/SH). Diet and fruit pomaces were chemically analyzed to assess polyphenol concentration and fibre fraction content. After the evaluation of growth performance, 6 birds/group were slaughtered at 35 days of age. Morphometric and histopathological investigations were performed on duodenum, jejunum and ileum. Excreta were collected to perform microbiota evaluation by 16S DNA sequencing. Weight, viscosity, enzymatic activity, short chain fatty acid (SCFAs) and ammonia concentration were determined in ileum and/or ceca content.

Results

A pomace and A diets showed the lowest polyphenol content and the highest content of soluble fibre fraction. No significant differences were observed for growth performance, gut morphometry and histopathology (P > 0.05). Dietary fruit pomace inclusion increased the weight of ileum and ceca and the ileum digesta viscosity (P < 0.05). In the ileum, A and S groups showed lower bacterial α-glucosidase activity than C groups. Moreover, small intestine SCFAs concentration was higher in fruit pomaces diets (P < 0.05). In ceca, B and S groups showed lower ammonia concentration and higher SCFAs than C. Dietary treatments also influenced the activity of α-glucosidase, α-galactosidase, β-galactosidase β-glucuronidase and xylase. Regarding microbiota, at phylum level, Firmicutes were differentially abundant across treatment (maximum for C and minimum in S, FDR > 0.05). At genus level, an increase of Weissella in AH and Erwinia in S/B diets, as well as a decrease of Lactobacillus in all fruit pomace groups were recorded (P < 0.05).

Conclusions

Fruit pomaces could be suitable ingredients in poultry nutrition even if further studies are needed to better understand which doses is more recommended to avoid negative effects on gut microbiota.

Dietary strawberry seed oil affects metabolite formation in the distal intestine and ameliorates lipid metabolism in rats fed an obesogenic diet

Objective

To answer the question whether dietary strawberry seed oil rich in α-linolenic acid and linoleic acid (29.3 and 47.2% of total fatty acids, respectively) can beneficially affect disorders induced by the consumption of an obesogenic diet.

Design

Thirty-two male Wistar rats were randomly assigned to four groups of eight animals each and fed with a basal or obesogenic (high in fat and low in fiber) diet that contained either strawberry seed oil or an edible rapeseed oil. A two-way analysis of variance was then applied to assess the effects of diet and oil and the interaction between them.

Results

After 8 weeks of feeding, the obesogenic diet increased the body weight and the liver mass and fat content, whereas decreased the cecal acetate and butyrate concentration. This diet also altered the plasma lipid profile and decreased the liver sterol regulatory element-binding protein 1c (SREBP-1c) content. However, the lowest liver SREBP-1c content was observed in rats fed an obesogenic diet containing strawberry seed oil. Moreover, dietary strawberry seed oil decreased the cecal short-chain fatty acid concentrations (acetate, propionate, and butyrate) regardless of the diet type, whereas the cecal β-glucuronidase activity was considerably increased only in rats fed an obesogenic diet containing strawberry seed oil. Dietary strawberry seed oil also lowered the liver fat content, the plasma triglyceride level and the atherogenic index of plasma.

Conclusions

Strawberry seed oil has a potent lipid-lowering activity but can unfavorably affect microbial metabolism in the distal intestine. The observed effects are partly due to the synergistic action of the oil and the obesogenic diet.

Microbial transglutaminase alters the immunogenic potential and cross-reactivity of horse and cow milk proteins

Horse milk is a valuable raw material and a very attractive alternative for scientific research to address the issue of cow milk (CM) allergy due to its protein profile. A decrease in immunoreactive properties can be achieved by thermal, enzymatic, and hydrolytic processing. Therefore, the aim of this study was to explore the possibility of reducing the immunoreactivity of horse milk proteins by microbial transglutaminase (TG) polymerization. To determine how TG linking alters immunoreactivity under simulated digestion of the examined milk, analyses were performed before, during, and after digestion. The dose-dependent (1, 10, and 100 U) effects of microbial TG on horse and cow milk were analyzed. A consecutive 3-stage digestion was simulated with salivary, gastric, and intestinal fluids. The effects of digestion were analyzed by SDS-PAGE, particle size analysis, and size-exclusion chromatography. Immunoreactivity was assessed using competitive ELISA (β-lactoglobulin and α-casein) and immunodot (sera from 7 patients aged 3 to 13 years who are allergic to CM proteins). Horse milk contained almost half of the amount of total proteins in CM. The dose 1 U/g of total milk protein changed the immunoreactivity of both cow and horse milk. With increasing TG doses, α-casein immunoreactivity increased, and β-lactoglobulin decreased. After total digestion, horse milk was characterized by 2.4-fold lower average IgE and 4.8-fold lower IgG reactivity than CM. We found that TG alters the IgE and IgG reactivity of CM after in vitro digestion. Horse milk was less reactive to IgE and IgG than was CM, with animal and patient sera. The effect of TG on immunoreactivity depends on enzyme quantity and milk protein type. The diet based on modified horse milk proteins could be an alternative for some patients with CM protein allergy; however, confirmation through clinical trials is needed.

Raspberry Polyphenolic Extract Regulates Obesogenic Signals in Hepatocytes

The aim of this in vitro study was to examine the effect of raspberry polyphenolic extract on the immune-metabolic molecular mechanisms activated by obesity-related signals in hepatocytes (HB-8965^®). Alterations in endosomal/lysosomal activity (neutral red uptake assay, NR), the expression of selected genes involved with lipid oxidation, and metabolism and inflammation processes in the liver were studied. Hepatocytes were treated with plasma collected from Wistar rats that were fed a high-fat diet (HF), raspberry polyphenolic extract (PP), serine-type protease inhibitors as an agonist of TLR4 (TD) or a combination of PP with HF or TD treatments. The PP added to the experimental treatments modulated hepatic immune-metabolic mechanisms through the upregulation of STAT1, ANGPTL4, and CD44, as well as considerably reducing the NR uptake and downregulation of COX-2 and the multifunctional protein AhR. The kinetic analysis of AhR expression revealed that HF-related molecular mechanisms activated AhR mRNA expression earlier than PP initiated the regulatory effect. In conclusion, PP might be considered a valuable dietary agent that regulates obesity-related signals in hepatocytes. Moreover, taking AhR kinetic behavior into consideration, it can be assumed that PP might modulate the severity of the HF-induced downstream metabolic signaling of AhR.

The effect of the high-fat diet supplemented with various forms of chromium on rats body composition, liver metabolism and organ histology Cr in liver metabolism and histology of selected organs

BACKGROUND

In the present study, we hypothesized that feeding rats a high-fat diet negatively affects liver metabolism and function and disturbs the histology of some internal organs. We also postulated that there is a form of chromium whose administration alleviates the negative effects of a high-fat diet in rats.

METHODS

To verify the hypotheses, we tested the effect of various forms of chrome (picolinate - Cr-Pic, Chromium(III)-methionine complex - Cr-Met, and chrome nanoparticles - Cr-NPs) applied in the recommended amount of 0.3 mg/kg of BW on growth parameters, body fat, liver metabolism and functional disorders, and histological parameters of selected internal organs in rats fed a standard (S) or high-fat diet (F). The experiment was conducted on 56 male outbred Wistar rats (Rattus norvegicus. Cmdb:WI) randomly divided into eight experimental groups. For eight weeks the rats received a standard or high-fat diet, without Cr or with Cr at 0.3 mg/kg diet in the form of Cr-Pic, Cr-Met or Cr-NPs.

RESULTS AND CONCLUSION

The use of a F diet disrupted the lipid-carbohydrate profile, worsened liver metabolism and function, reduced the expression of hepatic PPAR-α and leaded to negative changes in the histological image of internal organs - liver, kidneys and pancreas. The 8-week use of an chromium supplement in a F diet, regardless of the form used, did not improve the ratio of fat tissue to lean tissue, worsened liver function and negatively affected on the histological image of the liver, kidneys and pancreas. However, the most negative changes in lipid-carbohydrate metabolism and liver functioning were observed with CrNPs supplementation.