Identification of key phenolic compounds responsible for antioxidant activities of free and bound fractions of blackberry varieties' extracts by boosted regression trees.

BACKGROUND: Free fractions of different blackberry varieties' extracts are high in phenolic compounds with antioxidant activities. However, the phenolic profiles and antioxidant activities against peroxyl radicals of bound fractions of different blackberry varieties' extracts have not been previously reported. In addition, what the key antioxidant phenolic compounds are in free and bound fractions of blackberry extracts remain unknown. This study aimed to investigate the phenolic profiles and antioxidant activities of free and bound fractions of eight blackberry varieties' extracts and reveal the key antioxidant phenolic compounds by boosted regression trees. RESULTS: Fifteen phenolics (three anthocyanins, four flavonols, three phenolic acids, two proanthocyanidins, and three ellagitannins) were identified in blackberry by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Ferulic acid, ellagic acid, procyanidin C1, kaempferol-O-hexoside, ellagitannins hex, and gallic acid were major bound phenolics. Bound fractions of eight blackberry varieties' extracts were high in phenolics and showed great antioxidant activity. Boosted regression trees analysis showed that cyanidin-3-O-glucoside and chlorogenic acid were the most significant compounds, contributing 48.4% and 15.9% respectively to the antioxidant activity of free fraction. Ferulic acid was the most significant antioxidant compound in bound fraction, with a contribution of 61.5%. Principal component analysis showed that Kiowa was the best among the eight varieties due to its phenolic profile and antioxidant activity. CONCLUSION: It was concluded that blackberry varieties contained high amounts of bound phenolics, which confer health benefits through reducing oxidative stress. Ferulic acid was the key compound to explain the antioxidant activities of bound fractions. © 2021 Society of Chemical Industry.

Effect of bovine serum albumin on the stability and antioxidant activity of blueberry anthocyanins during processing and in vitro simulated digestion.

The application of blueberry anthocyanins (ANs) was limited due to their low in-process stability and bioavailability. In our study, the stability and antioxidant capacity of ANs before and after adding bovine serum albumin (BSA) were examined by simulating various processing, storage (light, sucrose, and vitamin C (Vc)), and in vitro simulated digestion parameters. For this purpose, pH-differential method, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), peroxyl scavenging capacity assay, and cellular antioxidant assay were conducted. BSA at different concentrations, specifically at 0.15 mg/mL, inhibited the degradation of ANs and the loss of antioxidant capacity. The results suggest that BSA has a positive effect on ANs.

Effect of Blueberry Anthocyanin-Rich Extracts on Peripheral and Hippocampal Antioxidant Defensiveness: The Analysis of the Serum Fatty Acid Species and Gut Microbiota Profile.

The current study investigated the positive effects of blueberry anthocyanin-rich extracts (BAE) on either peripheral or hippocampal antioxidant defensiveness and established the connection of the improved antioxidant status with the altered fatty acid species and gut microbiota profile. High-fat diet-induced oxidative stress in C57BL/6 mice was attenuated by BAE administration, which was reflected by strengthened antioxidant enzymes, alleviated hepatic steatosis, and improved hippocampal neuronal status. Serum lipidomics analysis indicated that the fatty acid species were altered toward the elevated unsaturated/saturated ratio, along with phospholipid species toward enriched n-3 polyunsaturated fatty acid compositions. The modulated antioxidant pattern could be attributed to the increased bacteria diversity, stimulated probiotics (Bifidobacterium and Lactobacillus) and short-chain fatty acid (SCFA) producers (Roseburia, Faecalibaculum, and Parabacteroides) improved by anthocyanins and their metabolites, which improved the colon environment, characterized by promoted SCFAs, restored colonic mucosa, and reorganized microbial structure. Thus, anthocyanin-rich dietary intervention is a promising approach for the defensiveness in human oxidative damage and neurodegeneration.

Bioactive flavonoids from Rubus corchorifolius inhibit α-glucosidase and α-amylase to improve postprandial hyperglycemia.

This research established an optimized method for the extraction and enrichment of flavonoids from R. corchorifolius fruit. Under the optimized extraction conditions, 12 flavonoids (1-12) were isolated, of which six (2-4, 9-10, 12) were obtained from R. corchorifolius for the first time. Compound 4 showed significant α-glucosidase (4.96 µM) and α-amylase (8.04 µM) inhibitory effects. Molecular modeling revealed that compound 4 exhibits strong binding with the active sites of α-glucosidase and α-amylase. Lineweaver-Burk plot analysis and surface plasmon resonance revealed the possible dynamic binding mechanism of the flavonoids with α-glucosidase and α-amylase. The enriched flavonoids and compound 4 showed significant hypoglycemic effects in mice administered a high dose of glucose. In this study, a variety of flavonoids with hypoglycemic activity were found for the first time, revealing the rich chemical composition of R. corchorifolius fruit and highlighting the potential value of R. corchorifolius fruit flavonoids as dietary supplements.

Effects of α-casein and ß-casein on the stability, antioxidant activity and bioaccessibility of blueberry anthocyanins with an in vitro simulated digestion.

Blueberry anthocyanins are well-known for their diverse biological functions. However, the instability during digestion results in their weak bioavailability. The current study aimed to investigate the alteration in the stability, antioxidant capacity and bioaccessibility of blueberry anthocyanins with the addition of α-casein and ß-casein in a simulated digestion system using pH differential method, HPLC-MS analysis, peroxyl scavenging capacity (PSC) assay, cellular antioxidant activity (CAA) and penetration test. The results showed that both α-casein and ß-casein could increase the stability of blueberry anthocyanins during intestinal digestion and protect their antioxidant capacity. Moreover, the addition of α-casein or ß-casein would enhance the bioaccessibility of blueberry anthocyanins. In conclusion, our study highlights that the interaction between α-casein or ß-casein with blueberry anthocyanins can protect the compounds against influences associated with the simulated digestion.

Serum Ceramide Reduction by Blueberry Anthocyanin-Rich Extract Alleviates Insulin Resistance in Hyperlipidemia Mice.

Blueberry anthocyanin-rich extract (BAE) was supplemented to high-fat diet (HFD)-fed mice to investigate sphingolipid metabolism modulating factors involved in the attenuated hyperinsulinemia and hyperlipidemia. A BAE-containing diet effectively controlled food intake and liver weight and significantly attenuated insulin resistance triggered by a HFD. Higher BAE (200 mg/kg of body weight) administration performed more efficiently in the improvement of hepatic steatosis and adipocyte hypertrophy, together with distinct suppressions in serum triacylglycerol and cholesterol in total and species. Serum lipid compositions revealed 200 mg/kg of BAE supplementation remarkably suppressed ceramide accumulation. Consistently, genes encoding enzymes associated with sphingomyelin conversion and ceramide de novo synthesis were modulated toward a healthy direction for restrained sphingolipid accumulation. Further, the inhibited mRNA expressions of protein phosphatase 2A and protein kinase Cζ involved in blocking Akt phosphorylation connected the controlled ceramides with the restored insulin sensitivity.

Identification of Cyanidin-3-arabinoside Extracted from Blueberry as a Selective Protein Tyrosine Phosphatase 1B Inhibitor.

Protein tyrosine phosphatase 1B (PTP1B) is an important target for type 2 diabetes. PTP1B inhibitors can reduce blood glucose levels by increasing insulin sensitivity. Anthocyanins often play a hypoglycemic effect, but the research about them have mainly focused on glucosidase. At present, the research about protein tyrosine phosphatase 1B (PTP1B) target is less, and the corresponding molecular mechanism is still unclear. Therefore, in this present study, anthocyanins isolated from blueberry were used to study the inhibitory activity on PTP1B. The isolated cyanidin-3-arabinoside (Cya-3-Ara) exhibited a better inhibitory activity with IC50 = 8.91 ± 0.63 µM, which was higher than the positive control (oleanolic acid, IC50 = 13.9 ± 1.01 µM), and the mechanism of PTP1B inhibition was reversible mixed pattern. The structure-activity relationship (SAR) between anthocyanins and PTP1B inhibition was investigated. The enzyme activity inhibition and molecular docking showed that anthocyanins had high selectivity for PTP1B inhibition. Further study showed that Cya-3-Ara could promote glycogen synthesis through ameliorating PTP1B-involved IRS-1/PI3K/Akt/GSK3ß pathways. Cya-3-Ara could also be regarded as a synergistic inhibitor (CI ≤ 0.54) of oleanolic acid to obtain a better inhibitory effect on PTP1B. Taken together, our study clearly illustrates the SAR between anthocyanins and PTP1B inhibition and the mechanism of Cya-3-Ara in the insulin signaling pathway.

Effect of In Vitro Digestion on Phytochemical Profiles and Cellular Antioxidant Activity of Whole Grains.

Most of the previous in vitro digestion treatments were conducted directly to whole grains without extraction of free phenolics, thus the bioaccessible phenolics contained both free phenolics that survived the digestion and digested phenolics released by digestion. However, the profiles of digested phenolics released by digestion remain unknown. This study was designed to investigate the phytochemical contents, peroxyl radical scavenging capacities (PSCs), and cellular antioxidant activities (CAAs) of free, digested, and bound fractions of whole grains. Total phenolic contents of whole grains were highest in digested fraction, followed by free and bound fractions. The predominant phenolics were 12 phenolic acids and one flavonoid, which mostly existed in bound forms, then in digested and free forms. The digested phenolics bound to proteins were in conjugated form. The bound fractions had the highest PSCs, followed by free and digested fractions. CAAs were highest in bound fractions, followed by digested and free fractions.

γ-Aminobutyric Acid Attenuates High-Fat Diet-Induced Cerebral Oxidative Impairment via Enhanced Synthesis of Hippocampal Sulfatides.

Long-term high-fat diet (HFD) in rats triggered cerebral oxidative stress, reflected by reactive oxygen species accumulation and antioxidant decline in peripheral and cerebral tissues, together with hippocampal lipid disturbance, particularly for triglyceride accumulation and sulfatide deficiency. Hippocampal formation and cerebral cortex also exhibited pathological changes, characterized by neurofibrillary tangle and reduced Nissl bodies. Sulfatides were noted to protect hippocampal neurons from oxidative damage through the clearance of ß-amyloid protein, with apolipoprotein E transporting and low-density lipoprotein receptor binding. Delightedly, we found γ-aminobutyric acid (GABA) supplement delivered by rice bran to rats significantly promoted hippocampal sulfatide synthesis and reversed the HFD-induced sulfatide deficiency and oxidative-triggered cerebral impairment. Elevated GABA concentration in hippocampus and the activation of GABA B-type receptors might be the primary contributors. This study demonstrated the potential of GABA-enriched rice bran as a novel dietary supplement to enhance a sulfatide-based therapeutic approach for neurodegenerative diseases in the early stages.

Blueberry Malvidin-3-galactoside Suppresses Hepatocellular Carcinoma by Regulating Apoptosis, Proliferation, and Metastasis Pathways In Vivo and In Vitro.

Anthocyanin, a natural antioxidant, is reported to have cytotoxicity against cancer cells; however, the mechanism remains unclear. The aim of the present study was to investigate the mechanism by which malvidin-3-galactoside (M3G), the prominent anthocyanin in blueberry, suppresses the development of hepatocellular carcinoma. In vitro, M3G suppressed the proliferation, polarization, migration, and invasion activities of HepG2 cells by regulating the protein expression of cyclin D1, cyclin B, cyclin E, caspase-3, cleaved caspase-3, Bax, p-JNK, and p-p38, activating phosphatase and tensin homologue deleted on chromosome 10 (PTEN), accompanied by a decrease in the p-AKT level, and lowering the protein expression levels of MMP-2 and MMP-9. In vivo, M3G promoted the apoptosis of liver tumor cells, as determined by immunohistochemistry (cleaved caspase-3, Ki-67, PTEN, and p-AKT), a terminal deoxynucleotidyl transferase dUTP nick end labeling assay, and hematoxylin-eosin staining. Overall, these results suggest that M3G, as an adjuvant ingredient or nutritional supplement, may be beneficial for liver cancer prevention and the modulatory mechanism seems to be associated with inhibition of proliferation, apoptosis, migration, and invasion-related pathways.

Active substance fractions and effects of Shugan Hewei Tang on hippocampal meurotransmitters in rat model of chronic stress-induced depression / 中国中药杂志

To study the antidepressant effect of Shugan Hewei Tang on chronic stress depression model rats, and select the effective substance fractions. Several male SD rats were randomly divided into 17 groups: blank control group, model group, positive control group(fluoxetine), Shugan Hewei Tang high and low dose groups, 6 high and low dose groups of different substance fractions. After modeling for 3 weeks and administration for 1 week, the effective substance fractions were selected according to the body mass and behavioral performance of SD rats in each group; several neurotransmitters in hippocampus of rats were determined by LC-MS/MS method, including norepinephrine(NE), serotonin(5-HT), 5-indoleacetic acid(5-HIAA), r-aminobutyric acid(GABA), and glutamic acid(Glu). Behavioral results after modeling showed that as compared with the blank group, the body mass growth of the model group was significantly reduced(P<0.01); the sugar water consumption was reduced(P<0.01); the distance between the open field and the number of crossing the central area were also significantly reduced(P<0.01, P<0.01); the resting time was increased significantly(P<0.01); and the forced swimming time was significantly prolonged(P<0.01), indicating that the depression model was effective. After intragastric administration, as compared with the model group, the above detection indicators of volatile oils, total polysaccharides and terpenoid in Fluoxetine, Shugan Hewei Tang groups were all changed(P<0.05 or P<0.01). The levels of NE, 5-HT and GABA in the hippocampus of the model group were significantly lower than those in the blank group(P<0.01), and the levels of 5-HIAA and Glu were significantly increased(P<0.01). As compared with the model group, neurotransmitters of the treatment groups were changed obviously or significantly(P<0.05 or P<0.01). Shugan Hewei Tang showed obvious anti-depressant effects, and the volatile oils, total polysaccharides and terpenoids acted as the main active substances. The mechanism of anti-depression may be related to its regulation of various neurotransmitter levels in the hippocampus.

Gamma-aminobutyric Acid Enriched Rice Bran Diet Attenuates Insulin Resistance and Balances Energy Expenditure via Modification of Gut Microbiota and Short-Chain Fatty Acids.

In this study, gamma-aminobutyric acid (GABA) enriched rice bran (ERB) was supplemented to obese rats to investigate the attenuation of metabolic syndromes induced by high-fat diet. ERB-containing diet stimulated butyrate and propionate production by promoting Anaerostipes, Anaerostipes sp., and associated synthesizing enzymes. This altered short-chain fatty acid (SCFA) distribution further enhanced circulatory levels of leptin and glucagon-like peptide-1, controlling food intake by downregulating orexigenic factors. Together with the enhanced fatty acid ß-oxidation highlighted by Prkaa2, Ppara, and Scd1 expression via AMPK signaling pathway and nonalcoholic fatty liver disease pathway, energy expenditure was positively modulated. Serum lipid compositions showed ERB supplement exhibited a more efficient effect on lowering serum sphingolipids, which was closely associated with the status of insulin resistance. Consistently, genes of Ppp2r3b and Prkcg, involved in the function of ceramides in blocking insulin action, were also downregulated following ERB intervention. Enriched GABA and phenolic acids were supposed to be responsible for the health-beneficial effects.

Serum phospholipid omega-3 polyunsaturated fatty acids and insulin resistance in type 2 diabetes mellitus and non-alcoholic fatty liver disease.

AIMS: To investigate the relationship between serum phospholipid omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and insulin resistance (IR) in patients with type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD). METHODS: 51 patients with T2DM and NAFLD (T2DM+NAFLD group), 50 with T2DM alone (T2DM group), 45 with NAFLD alone (NAFLD group), and 42 healthy control subjects (NC group) were studied. Serum ω-3 PUFA profiles were analyzed by gas chromatography, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), and serum lipid concentrations were measured. Insulin resistance was assessed by the homeostasis model assessment method (HOMA-IR). RESULTS: HOMA-IR levels were higher in the T2DM+NAFLD group than in the T2DM, NAFLD and NC groups (p<0.05), as were ALT, AST, GGT, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) concentrations (p<0.05). Conversely, serum ω-3 PUFA levels were significantly lower in the T2DM+NAFLD group than in the other groups (p<0.05). The ω-3 PUFA level was negatively correlated with HOMA-IR, TC, LDL-C and TG. CONCLUSIONS: Serum phospholipid ω-3 PUFA levels were significantly decreased in patients with T2DM and NAFLD, and were negatively related with insulin resistance. Thus, reduced ω-3 PUFAs may play an important role in the development of T2DM and NAFLD.

Effect of acupuncture at different time points on kidney function and oxygen free radical metabolism in rats with simulated weightlessness / 中国针灸

<p><b>OBJECTIVE</b>To explore the effects of pre-acupuncture and immediate acupuncture on kidney function and oxygen free radical metabolism in rats with simulated weightlessness.</p><p><b>METHODS</b>Twenty male clean-grade Wister rats were randomly divided into a normal control group, a model group, a pre-acupuncture group and an immediate acupuncture group, 5 rats in each one. The rats in the normal control group did not receive any treatment but free activities for 4 weeks. The rats in the rest groups received 4-week tail suspension to establish the model of simulated weightlessness. One week before the tail suspension, the rats in the pre-acupuncture group were treated with electroacupuncture at "Shenshu" (BL 23), "Pishu" (BL 20) and "Sanyinjiao" (SP 6) for 30 min per treatment, once a day for 7 days. The rats in the immediate acupuncture group received tail suspension and acupuncture at the same time; during the tail suspension, the electroacupuncture was applied at "Shenshu" (BL 23), "Pishu" (BL 20) and "Sanyinjiao" (SP 6) for 30 min per treatment, once every other day for 14 days. The colorimetric method was used to measure the content of blood urea nitrogen (BUN) in serum as well as activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) and content of malonaldehyde (MDA) in renal tissue in each group.</p><p><b>RESULTS</b>Compared with the normal control group, the content of BUN in the model group was increased significantly (P<0.01), the activity of SOD and GSH-PX in nephridial tissue was significantly reduced (both P<0.01), and the content of MDA was increased significantly (P<0.05). Compared with the model group, the content of BUN in the pre-acupuncture group and immediate acupuncture group was significantly reduced (P<0.01, P<0.05), the activity of GSH-PX in the pre-acupuncture group was obviously increased (P<0.05) and the content of MDA in the immediate acupuncture group was increased significantly (P<0.01). Compared with the immediate acupuncture group, the content of MDA in the pre-acupuncture group was lower (P<0.01).</p><p><b>CONCLUSION</b>The pre-acupuncture and immediate acupuncture both have the capacity to improve the kidney function and anti-oxygen free radical injury in rats with simulated weightlessness, however, the capacity to increase the protection ability of the kidney and eliminate free radical in the pre-acupuncture group is superior to that in the immediate acupuncture group, which is likely to be related with improving antioxidant ability of kidney.</p>

Effect of acupuncture on the p53 protein expression of mice with Alzheimer's disease / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of acupuncture method for benefiting qi, regulating blood, supplementing the root, and cultivating the essence (BQRBSRCE) on the p53 protein expression of mice with Alzheimer's disease (AD).</p><p><b>METHODS</b>SAMP8 mice were divided into the control group, the acupuncture group, and the non-acupoint group. The homologous SAMR1 control group was set up. Mice in the acupuncture group used acupuncture method for BQRBSRCE by needling at Tanzhong (RN17), Zhongwan (RN12), Qihai (RN6), and bilateral Xuehai (SP10), and bilateral Zusanli (ST36).Two fixed non-acupoints from bilateral ribs were needled in the non-acupoint group. The p53 protein expression in the cortex and hippocampus of mice was determined using Western blot. The pathological changes of neurons in the hippocampal CA1 region, the temporal lobe, and the occipital lobe were observed using HE staining. The expression of cortical p53-positive cells was detected by immunohistochemical assay.</p><p><b>RESULTS</b>The p53 protein was highly expressed in the cortex of SAMP8, which was significantly down-regulated after acupuncture, showing statistical difference when compared with the SAMP8 control group (P < 0.05), but with no statistical difference when compared with the SAMR1 control group (P > 0.05). Needling at non-acupoints had no obvious effect on the p53 protein expression. There was no statistical difference in the p53 protein expression of the hippocampus (P > 0.05).</p><p><b>CONCLUSION</b>Acupuncture method for BQRBSRCE could down-regulate the p53 protein expression in the brain of mice, improve the pathological state of brain cells, thus enhancing learning and memory capabilities of AD mice, improving their cognitive functions, with specificity of acupoints.</p>

[Serum omega-3 polyunsaturated fatty acid and insulin resistance in type 2 diabetes mellitus and non-alcoholic fatty liver disease].

OBJECTIVE: To investigate the relationship between serum omega-3 polyunsaturated fatty acid (omega-3PUFA) and insulin resistance (IR) in patients with type 2 diabetes mellitus and non-alcoholic fatty liver disease (NAFLD). METHODS: This trial involved 51 patients of type 2 diabetes mellitus with NAFLD (G4 group), 50 patients of type 2 diabetes alone (G3 group), 45 patients of NAFLD alone (G2 group) and 42 healthy control subjects (G1 group). Serum omega-3PUFA profile was analyzed with capillary gas chromatography. Insulin resistance was assessed by homeostasis model assessment (HOMA-IR). ALT, AST, gamma-glutamyltransferase (GGT) and serum lipids were measured. RESULTS: The levels of HOMA-IR were higher in G4 group than those in G3, G2 and G1 group (4.90 + or - 2.54 vs 2.38 + or - 1.23, 2.20 + or - 1.15, 1.13 + or - 0.42; P < 0.05). The level of ALT, AST, GGT, TC, TG, LDL-C were higher in G4 group than those in G3, G2 and G1 group (P < 0.05). The level of omega-3PUFA was significantly lower in G4 group than those in G3, G2 and G1 group (5.68 + or - 2.02 vs 7.17 + or - 2.38, 6.97 + or - 2.32, 10.08 + or - 2.76; P < 0.05). omega-3PUFA concentration was negatively correlated with HOMA-IR, TC, TG and LDL-C (r = -0.491, -0.376, -0.462, -0.408, P < 0.05). CONCLUSIONS: Serum omega-3PUFA is significantly decreased in patients with type 2 diabetes mellitus and NAFLD. Serum omega-3PUFA is negatively correlated with insulin resistance. omega-3PUFA plays a very important role in the development of diabetes mellitus and NAFLD.