Micro-Executor of Natural Products in Metabolic Diseases

Obesity, diabetes, and cardiovascular diseases are the major chronic metabolic diseases that threaten human health. In order to combat these epidemics, there remains a desperate need for effective, safe, and easily available therapeutic strategies. Recently, the development of natural product research has provided new methods and options for these diseases. Numerous studies have demonstrated that microRNAs (miRNAs) are key regulators of metabolic diseases, and natural products can improve lipid and glucose metabolism disorders and cardiovascular diseases by regulating the expression of miRNAs. In this review, we present the recent advances involving the associations between miRNAs and natural products and the current evidence showing the positive effects of miRNAs for natural product treatment in metabolic diseases. We also encourage further research to address the relationship between miRNAs and natural products under physiological and pathological conditions, thus leading to stronger support for drug development from natural products in the future.

miR-363-3p/PTEN is involved in the regulation of lipid metabolism by genistein in HepG2 cells via ERβ

BACKGROUND

Genistein (GEN) is one of the most well-known phytoestrogens identified in various legumes. Although increasing evidence shows GEN has a potential use in phytotherapy to regulate lipid metabolism, its therapeutic mechanisms have not yet been completely elucidated, especially epigenetic alterations of miRNAs to alleviate lipid accumulation in the liver remains unknown.

PURPOSE

To clarify how GEN modulates the miRNA profile in HepG2 cells and investigate molecular mechanisms of the modulated miRNA on regulating hepatic lipid metabolism.

METHODS

The miRNA microarray was performed to compare the miRNAs expression patterns, followed by determining principal miRNA and its target gene associated with hepatic lipid metabolism modulated by GEN. miR-363-3p mimics (mi) and phosphatase and tensin homolog (PTEN)-siRNA were transfected into HepG2 cells and GEN was further treated with the cells for 24 h RESULTS: GEN induced downregulation of miR-363-3p and upregulation of PTEN, which was a target mRNA of miR-363-3p. The miR-363-3p mi led to an upregulation of sterol-regulatory element-binding protein-1c (SREBP-1c) and its downstream lipid synthesis-related factors in HepG2 cells. In addition, the inhibition of PTEN led to an increase of lipogenesis, which was associated with the AKT/mTOR signal regulation. However, GEN treatment could abrogate the lipogenic effects of miR-363-3p mi or PTEN siRNA. The modulation was associated with estrogen receptor β (ERβ).

CONCLUSION

We discerned a new mechanism that GEN regulated hepatic lipid metabolism by inhibiting miR-363-3p, which could be mediated via ERβ and by targeting PTEN in HepG2 cells. Additionally, GEN reduced hepatic lipid accumulation by regulating PTEN-AKT/mTOR signal. It implicated a protective role of GEN by elucidating its epigenetic modification of the miRNA modulated by ERβ on improving hepatic lipid metabolism and provided novel evidence of the mechanism on targeting miR-363-3p/PTEN in treating hepatic lipid disorders.

Effects of miR-33 Deficiency on Metabolic and Cardiovascular Diseases: Implications for Therapeutic Intervention

MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptionally inhibit gene expression. These small molecules are involved in several biological conditions such as inflammation, cell growth and proliferation, and regulation of energy metabolism. In the context of metabolic and cardiovascular diseases, miR-33 is of particular interest as it has been implicated in the regulation of lipid and glucose metabolism. This miRNA is located in introns harboured in the genes encoding sterol regulatory element-binding protein (SREBP)-1 and SREBP-2, which are key transcription factors involved in lipid biosynthesis and cholesterol efflux. This review outlines the role of miR-33 in a range of metabolic and cardiovascular pathologies, such as dyslipidaemia, nonalcoholic fatty liver disease (NAFLD), obesity, diabetes, atherosclerosis, and abdominal aortic aneurysm (AAA), and it provides discussion about the effectiveness of miR-33 deficiency as a possible therapeutic strategy to prevent the development of these diseases.

Magnetic nanometer combined with microwave: Novel rapid thawing promotes phenolics release in frozen-storage lychee

Magnetic nanometer combined with microwave thawing (MN-MT) could become a novel solution to challenges uneven and overheating of microwave thawing (MT), while retaining high thawing efficiency, compared to conventional water immersion thawing (WT). In this study, MN-MT was applied to thaw fruit (lychee as an example) for the first time, and was evaluated by comparison with WT, MT and water immersion combined with microwave thawing (WI-MT). Results showed that MN-MT could significantly shorten the thawing time of frozen lychee by 80.67%, 25.86% and 18.83% compared to WT, MT and WI-MT, respectively. Compared to WT, MN-MT was the only thawing treatment which significantly enhanced the release of quercetin-3-O-rutinose-7-O-α-l-rhamnoside, according to HPLC-DAD. Meanwhile, thermal-sensitive procyanidin B2, phenylpropionic acid and protocatechuic acid were found to be protected from degradations only by MN-MT based on UPLC-ESI-QTOF-MS/MS results. In summary, MN-MT is a potential novel treatment for rapid thawing and quality maintenance of frozen fruits.

Mesenchymal stem cell-derived exosomes and non-coding RNAs: Regulatory and therapeutic role in liver diseases

Liver disease has become a major health problem worldwide due to its high morbidity and mortality. In recent years, a large body of literature has shown that mesenchymal stem cell-derived exosomes (MSC-Exo) are able to play similar physiological roles as mesenchymal stem cells (MSCs). More importantly, there is no immune rejection caused by transplanted cells and the risk of tumor formation, which has become a new strategy for the treatment of various liver diseases. Moreover, accumulating evidence suggests that non-coding RNAs (ncRNAs) are the main effectors by which they exert hepatoprotective effects. Therefore, by searching the databases of Web of Science, PubMed, ScienceDirect, Google Scholar and CNKI, this review comprehensively reviewed the therapeutic effects of MSC-Exo and ncRNAs in liver diseases, including liver injury, liver fibrosis, and hepatocellular carcinoma. According to the data, the therapeutic effects of MSC-Exo and ncRNAs on liver diseases are closely related to a variety of molecular mechanisms, including inhibition of inflammatory response, alleviation of liver oxidative stress, inhibition of apoptosis of hepatocytes and endothelial cells, promotion of angiogenesis, blocking the cell cycle of hepatocellular carcinoma, and inhibition of activation and proliferation of hepatic stellate cells. These important findings will provide a direction and basis for us to explore the potential of MSC-Exo and ncRNAs in the clinical treatment of liver diseases in the future.

Hepato-Protective Effects of Delta-Tocotrienol and Alpha-Tocopherol in Patients with Non-Alcoholic Fatty Liver Disease: Regulation of Circulating MicroRNA Expression

MicroRNAs (miRNAs) play a key role in the regulation of genes for normal metabolism in the liver. Dysregulation of miRNAs is involved in the development and progression of non-alcoholic fatty liver disease (NAFLD). We aimed to explore changes in circulating miRNA expression in response to delta-tocotrienol (δT3) and alpha-tocopherol (αTF) supplementation and correlate them with relevant biochemical markers in patients with NAFLD. In total, 100 patients with NAFLD were randomized to either receive δT3 (n = 50) 300 mg or αTF (n = 50) 268 mg twice/day for 48 weeks. Plasma expression of miRNA-122, -21, -103a-2, -421, -375 and -34a were determined at baseline, 24 and 48 weeks of intervention using RT-qPCR. Both δT3 and αTF significantly downregulated expression of miRNA-122, -21, -103a-2, -421, -375 and -34a. Moreover, δT3 was more effective than αTF in reducing expression of miRNA-375 and -34a. A significant correlation was observed between miRNA expression and biochemical markers of hepatic steatosis, insulin resistance (IR), oxidative stress (OS), inflammation and apoptosis. δT3 and αTF exert hepato-protective effects by downregulating miRNAs involved in hepatic steatosis, IR, OS, inflammation and apoptosis in patients with NAFLD. Furthermore, δT3 has more pronounced effects than αTF in reducing miR-375 and miR-34a, which are linked to regulation of inflammation and apoptosis.

The Efficacy of Oligonol in Nonalcoholic Fatty Liver Disease: A Randomized Double-Blinded Placebo-Controlled Trial

Introduction: Oligonol, an oligomerized-polyphenol from Litchi chinensis extract, has been shown to alleviate metabolic syndrome. The aim of this study was to evaluate the effects of oligonol in patients with nonalcoholic fatty liver disease (NAFLD). Methods: Adult patients with NAFLD defined by magnetic resonance imaging-derived proton density fat fraction (MRI-PDFF) ≥11% were enrolled and then randomly assigned to receive either oligonol or placebo capsules. Primary endpoint was ≥30% reduction in MRI-PDFF at 24 weeks. Secondary outcomes were reductions in bodyweight, waist circumference, alanine transaminase, fasting blood sugar, and lipid profiles at week 24. Results: Forty patients were enrolled (n = 20/group). Primary endpoint was achieved in 20% in the oligonol group and 15% in the placebo group (p = 0.50). The authors found a reduction in MRI-PDFF between weeks 0 and 24 in the oligonol group; however, the change was not different from the placebo group. Secondary outcomes were similar between two groups. Discussion: Oligonol has not shown a significant therapeutic effect in NAFLD. Future studies with a longer duration of therapy might be needed to achieve the primary endpoint. Clinical Trial Registration Number: Thai Clinical Trial Registry identification number: TCTR20200814001.

Novel Catabolic Pathway of Quercetin-3-O-Rutinose-7-O-α-L-Rhamnoside by Lactobacillus plantarum GDMCC 1.140: The Direct Fission of C-Ring

Lychee pulp phenolics (LPP) is mainly catabolized in the host colon, increasing the abundances of Bacteroides and Lactobacillus. Herein, five selected gut microbial strains (Bacteroides uniformis, B. thetaiotaomicron, Lactobacillus rhamnosus, L. plantarum, and L. acidophilus) were separately incubated with LPP to ascertain the specific strains participating in phenolic metabolism and the corresponding metabolites. The results indicated that B. uniformis, L. rhamnosus, and L. plantarum were involved in LPP utilization, contributing to 52.37, 28.33, and 45.11% of LPP degradation after 48 h fermentation, respectively. Unprecedentedly, the metabolic pathway of the major phenolic compound quercetin-3-O-rutinose-7-O-α-L-rhamnoside by L. plantarum, appeared to be the direct fission of C-ring at C2–O1 and C3–C4 bonds, which was proved from the occurrence of two substances with the deprotonated molecule [M–H]⁻ ion at m/z 299 and 459, respectively. Meanwhile, it was fully confirmed that B. uniformis participated in the catabolism of isorhamnetin glycoside and procyanidin B2. In the B. uniformis culture, kaempferol was synthesized through dehydroxylation of quercetin which could be catabolized into alphitonin by L. rhamnosus. Furthermore, LPP metabolites exerted higher antioxidant activity than their precursors and gave clues to understand the interindividual differences for phenolic metabolism by gut microbiota.

Litchi (Litchi chinensis Sonn.): a comprehensive review of phytochemistry, medicinal properties, and product development

Since ancient times, litchi has been well recognized as a functional food for the management of various ailments. Many bioactives, including flavanoids, anthocyanins, phenolics, sesquiterpenes, triterpenes, and lignans, have been identified from litchi with a myriad of biological properties both in vitro and in vivo. In spite of the extensive research progress, systemic reviews regarding the bioactives of litchi are rather scarce. Therefore, it is crucial to comprehensively analyze the pharmacological activities and the structure-activity relationships of the abundant bioactives of litchi. Besides, more and more studies have focused on litchi preservation and development of its by-products, which is significant for enhancing the economic value of litchi. Based on the analysis of published articles and patents, this review aims to reveal the development trends of litchi in the healthcare field by providing a systematic summary of the pharmacological activities of its extracts, its phytochemical composition, and the nutritional and potential health benefits of litchi seed, pulp and pericarp with structure-activity relationship analysis. In addition, its by-products also exhibited promising development potential in the field of material science and environmental protection. Furthermore, this study also provides an overview of the strategies of the postharvest storage and processing of litchi.

Targeting miRNA by Natural Products: A Novel Therapeutic Approach for Nonalcoholic Fatty Liver

The increasing prevalence of nonalcoholic fatty liver disease (NAFLD) as multifactorial chronic liver disease and the lack of a specific treatment have begun a new era in its treatment using gene expression changes and microRNAs. This study aimed to investigate the potential therapeutic effects of natural compounds in NAFLD by regulating miRNA expression. MicroRNAs play essential roles in regulating the cell's biological processes, such as apoptosis, migration, lipid metabolism, insulin resistance, and adipocyte differentiation, by controlling the posttranscriptional gene expression level. The impact of current NAFLD pharmacological management, including drug and biological therapies, is uncertain. In this context, various dietary fruits or medicinal herbal sources have received worldwide attention versus NAFLD development. Natural ingredients such as berberine, lychee pulp, grape seed, and rosemary possess protective and therapeutic effects against NAFLD by modifying the gene's expression and noncoding RNAs, especially miRNAs.

Quercetin prevents cadmium chloride-induced hepatic steatosis and fibrosis by downregulating the transcription of miR-21

This study investigated if cadmium chloride (CdCl₂ )-induced hepatic steatosis and fibrosis and the protective effect of quercetin (QUR) are mediated modulating the activity of miR-21, a known hepatic lipogenic and fibrotic miRNA. Male rats (n = 8/group) were divided as control, control + QUR (50 mg/kg; orally), CdCl₂ (10 moml/L; drinking water), CdCl₂  + miR-21 antagomir (inhibitor) (16 mg/kg/first 3 days), and CdCl₂  + QUR (50 mg/kg). Treatments were conducted for 20 weeks, daily. All treatments showed no effect on fasting glucose and insulin levels. Administration of either miR-21 or QUR prevented CdCl₂ -induced hepatic damage, as well as lipid droplets and collagen deposition. They also reduced serum levels of ALT and AST and decreased serum and hepatic levels of total cholesterol, triglycerides, and low-density lipoproteins in CdCl₂ -treated rats. Concomitantly, they reduced hepatic levels of reactive oxygen species, malondialdehyde, interleukin-6, and tumor necrosis factor-α, suppressed the activation of NF-kb P65, and increased hepatic levels of nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione (GSH), and superoxide dismutase (SOD). These effects were associated with reduced expression of SREBP1, TGF-β1, Smad3, and collagen1 A and increased expression of PPARα, CPT1, and smad7. Interestingly, QUR significantly lowered levels of miR-21 and increased the protein levels and activity of Nrf2, as well as levels of GSH and SOD in the livers of both the control and CdCl₂ -treated rats. Of note, levels of Nrf2 were negatively correlated with the transcription of miR-21. In conclusion: QUR prevents CdCl₂ -induced hepatic steatosis and fibrosis mainly through attenuating its ability to upregulate miR-21, at least, by upregulation of Nrf2.

Silibinin improves nonalcoholic fatty liver by regulating the expression of miR‑122: An in vitro and in vivo study

Silibinin is a flavonoid that improves fatty liver and insulin resistance. To elucidate the effect of silibinin on lipid deposition and the potential molecular mechanism, the present study conducted in vivo and in vitro experiments. In the in vivo experiments, mice were randomly divided into control, high‑fat and silibinin groups, while HepG2 cells were randomly divided into control, palmitic acid intervention and silibinin intervention groups. The mRNA, protein and miR‑122 expression associated with hepatic lipid metabolism were detected in each group. The results demonstrated that silibinin reduced the triglyceride content, miR‑122 expression and the mRNA and protein expressions of fatty acid synthase (FAS) and acetyl‑CoA carboxylase (ACC). Silibinin increased the mRNA and protein expression of carnitine palmitoyl transferase 1A (CPT1A). In the present study, HepG2 cells cultured with palmitate were treated with silibinin following overexpression of micro RNA (miR) 122. The results demonstrated that the mRNA and protein expression of FAS and ACC was increased, while that of CPT1A was decreased. Therefore, it could be deduced that silibinin improved lipid metabolism by reducing the expression of miR‑122 and inhibiting the expression of miR‑122 may be a new therapeutic target to improve fatty liver disease.

Lychee (Litchi chinensis Sonn.) Pulp Phenolics Activate the Short-Chain Fatty Acid-Free Fatty Acid Receptor Anti-inflammatory Pathway by Regulating Microbiota and Mitigate Intestinal Barrier Damage in Dextran Sulfate Sodium-Induced Colitis in Mice

The preventive effect of lychee pulp phenolics (LPP) on dextran sulfate sodium (DSS)-induced colitis of mice and its underlying mechanisms were investigated in this research. LPP supplementation mitigated DSS-induced breakage of the gut barrier as evidenced by the increased tight junction proteins and the enhanced integrity of epithelial cells. Both LPP and 5-ASA treatments could downregulate the expressions of toll-like receptor 4 (TLR-4), NOD protein-like receptor 3 (NLRP3), and proinflammatory cytokines to normal levels. Notably, treatment with LPP at a dosage of 500 mg/kg/day effectively upregulated FFAR2 and FFAR3 expression and contents of short-chain fatty acids (SCFAs), suggesting the activation of the SCFA-FFAR (free fatty acid receptor) pathway. Consistently, the abundances of probiotic taxa and microbiota (Akkermansia, Lactobacillus, Coprococcus, and Bacteroides uniformis) associated with SCFA synthesis were elevated, whereas harmful bacteria (Enterococcus and Aggregatibacter) were suppressed. These data indicate that LPP ameliorates gut barrier damage, activates the microbiota-SCFA-FFAR signaling cascade, and suppresses the TLR4/NLRP3-NF-κB pathway, and therefore, LPP supplementation could be a promising way to protect the intestinal tract.

In vitro simulated digestion and colonic fermentation of lychee pulp phenolics and their impact on metabolic pathways based on fecal metabolomics of mice

Biochemical change and bioactivities of lychee pulp phenolics following simulated human digestion and in vivo metabolism in mice.

Rice Bran Phenolic Extract Confers Protective Effects against Alcoholic Liver Disease in Mice by Alleviating Mitochondrial Dysfunction via the PGC-1α-TFAM Pathway Mediated by microRNA-494-3p

The initiation and development of alcoholic liver disease (ALD) is mediated, at least partly, by mitochondria dysfunction, which is regulated by PPARγ coactivator-1α (PGC-1α) via mitochondria transcription factor A (TFAM). Then, PGC-1α expression was regulated by several microRNAs. This research investigated the hepatoprotective effects of the rice bran phenolic extract (RBPE) on mice fed with an ethanol-containing diet via the microRNAs-PGC-1α-TFAM signal pathway. RBPE treatment protected against alcoholic liver injury, as indicated by decreased serum aminotransferase activities and hepatic triglyceride accumulation, together with alleviated oxidative stress in serum and the liver. RBPE treatment alleviated ethanol-induced mitochondrial dysfunction through altering the membrane potential, mtDNA content, and respiratory chain complex enzyme activities in mitochondria, resulting in increased hepatic ATP production. Decreased cytoplasmic cytochrome c contents, caspase-3 activity, and Bax/Bcl-2 ratio were detected in the liver of RBPE-treated mice, indicating that the RBPE might inhibit ethanol-induced hepatocellular apoptosis. Furthermore, ethanol-induced decreases in the mRNA and protein expression of PGC-1α and TFAM were remarkably alleviated in RBPE-treated mice. RBPE treatment to ethanol-fed mice could also downregulate the expression of microRNA-494-3p, which regulates PGC-1α expression directly. Therefore, the RBPE might exert protection against ALD by alleviating mitochondrial dysfunction and the resulting hepatocyte apoptosis via the PGC-1α-TFAM signal pathway mediated by microRNA-494-3p.

Grape seed proanthocyanidin extract ameliorates hepatic lipid accumulation and inflammation in grass carp (Ctenopharyngodon idella)

Hepatic lipid metabolism disorder due to excessive fat accumulation in fish is a significant problem in aquaculture. Studies have shown that grape seed procyanidin extract (GSPE) can regulate fish lipid metabolism and improve fish immunity. However, the mechanism is unclear. In this study, we used grass carp that stores excess fat in the liver as a model. In vitro, GSPE treatment of hepatocytes for 3 h significantly decreased TG content, accompanied with decreased expression of SREBP-1c, FAS, and ACC and increased expression of PPARα, ATGL, and LPL. GSPE treatment for 1 h significantly decreased expression of pro-inflammatory cytokines (TNFα, IL-6, IL-1β, and NF-κB) and increased the expression of anti-inflammatory cytokines (IL-10 and TGF-β1). In vivo, the administration of GSPE significantly reduced high-fat diet-induced increase of serum CHOL, TG, and HDL, but increased LDL content. GSPE treatment for 3 h increased expression of ATGL and LPL, and significantly decreased the expression of HFD-fed-induced SREBP-1c, ACC, FAS, PPARγ, PPARα, and H-FABP. GSPE treatment for 3 h also significantly decreased the expression of pro-inflammatory cytokines (TNFα, IL-6, and IL-1β) and increased the expression of the anti-inflammatory cytokine IL-10. The expression levels of the lipogenic miRNAs, miR-33, and miR-122, were suppressed both in vivo and in vitro by GSPE. In summary, GSPE had hypolipidemic and potential anti-inflammatory effects in the liver, potentially mediated by miR-33 and miR-122.

Nutrient components, health benefits, and safety of litchi (Litchi chinensis Sonn.): A review

Litchi (Litchi chinensis Sonn.) is a tropical to subtropical fruit that is widely cultivated in more than 20 countries worldwide. It is normally consumed as fresh or processed and has become one of the most popular fruits because it has a delicious flavor, attractive color, and high nutritive value. Whole litchi fruits have been used not only as a food source but also for medicinal purposes. As a traditional Chinese medicine, litchi has been used for centuries to treat stomach ulcers, diabetes, cough, diarrhea, and dyspepsia, as well as to kill intestinal worms. Both in vitro and in vivo studies have indicated that whole litchi fruits exhibit antioxidant, hypoglycemic, hepatoprotective, hypolipidemic, and antiobesity activities and show anticancer, antiatherosclerotic, hypotensive, neuroprotective, and immunomodulatory activities. The health benefits of litchi have been attributed to its wide range of nutritional components, among which polysaccharides and polyphenols have been proven to possess various beneficial properties. The diversity and composition of litchi polysaccharides and polyphenols have vital influences on their biological activities. In addition, consuming fresh litchi and its products could lead to some adverse reactions for some people such as pruritus, urticaria, swelling of the lips, swelling of the throat, dyspnea, or diarrhea. These safety problems are probably caused by the soluble protein in litchi that could cause anaphylactic and inflammatory reactions. To achieve reasonable applications of litchi in the food, medical and cosmetics industries, this review focuses on recent findings related to the nutrient components, health benefits, and safety of litchi.

Targeting epigenetics in cancer: therapeutic potential of flavonoids

Irrespective of sex and age, cancer is the leading cause of mortality around the globe. Therapeutic incompliance, unwanted effects, and economic burdens imparted by cancer treatments, are primary health challenges. The heritable features in gene expression that are propagated through cell division and contribute to cellular identity without a change in DNA sequence are considered epigenetic characteristics and agents that could interfere with these features and are regarded as potential therapeutic targets. The genetic modification accounts for the recurrence and uncontrolled changes in the physiology of cancer cells. This review focuses on plant-derived flavonoids as a therapeutic tool for cancer, attributed to their ability for epigenetic regulation of cancer pathogenesis. The epigenetic mechanisms of various classes of flavonoids including flavonols, flavones, isoflavones, flavanones, flavan-3-ols, and anthocyanidins, such as cyanidin, delphinidin, and pelargonidin, are discussed. The outstanding results of preclinical studies encourage researchers to design several clinical trials on various flavonoids to ascertain their clinical strength in the treatment of different cancers. The results of such studies will define the clinical fate of these agents in future.

Hypolipidemic effects of protein hydrolysates from Trachinotus ovatus and identification of peptides implied in bile acid-binding activity using LC-ESI-Q-TOF-MS/MS

In the present work, analysis of the hypolipidemic properties of Trachinotus ovatus protein hydrolysates (TOPHs) and identification of peptides with bile acid-binding activity were performed. Hydrolysates prepared by trypsin digestion exhibited the highest in vitro bile acid-binding capacities compared with hydrolysates prepared with the other four proteases and were mainly composed of small peptides and amino acids with molecular weights <3 kDa, accounting for 77.30%. Among the five ultra-filtration fractions of TOPHs, TOPHs-5 (<3 kDa) exhibited the highest in vitro bile acid-binding capacity, which was equivalent to 77.97% of cholestyramine at the same concentration. A total of 68 peptides were identified from TOPHs-5 by LC-ESI-Q-TOF-MS/MS and 9 of them had hydrophobicity of more than 60%. These highly hydrophobic peptides might be associated with the bile acid-binding activity of TOPHs-5. In vivo experiments indicated that the TOPHs could effectively reduce total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and the atherogenic index (AI), while they could evidently increase the high-density lipoprotein cholesterol (HDL-C) content. Furthermore, TOPHs exerted a marked protective effect on hepatorenal function, as evidenced by decreased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatinine (CREA). Histopathological studies confirmed that TOPHs evidently protected the liver from histological alterations. In summary, for the first time, hypolipidemic effects and subsequential identification were obtained from TOPHs, which are promising natural ingredients that could potentially be employed in the management of hyperlipidemia.

The whole-transcriptome landscape of muscle and adipose tissues reveals the ceRNA regulation network related to intramuscular fat deposition in yak

Background

The Intramuscular fat (IMF) content in meat products, which is positively correlated with meat quality, is an important trait considered by consumers. The regulation of IMF deposition is species specific. However, the IMF-deposition-related mRNA and non-coding RNA and their regulatory network in yak (Bos grunniens) remain unknown. High-throughput sequencing technology provides a powerful approach for analyzing the association between transcriptome-related differences and specific traits in animals. Thus, the whole transcriptomes of yak muscle and adipose tissues were screened and analyzed to elucidate the IMF deposition-related genes. The muscle tissues were used for IMF content measurements.

Results

Significant differences were observed between the 0.5- and 2.5-year-old yaks. Several mRNAs, miRNAs, lncRNAs and circRNAs were generally expressed in both muscle and adipose tissues. Between the 0.5- and 2.5-year-old yaks, 149 mRNAs, 62 miRNAs, 4 lncRNAs, and 223 circRNAs were differentially expressed in muscle tissue, and 72 mRNAs, 15 miRNAs, 9 lncRNAs, and 211 circRNAs were differentially expressed in adipose tissue. KEGG annotation revelved that these differentially expressed genes were related to pathways that maintain normal biological functions of muscle and adipose tissues. Moreover, 16 mRNAs, 5 miRNAs, 3 lncRNAs, and 5 circRNAs were co-differentially expressed in both types of tissue. We suspected that these co-differentially expressed genes were involved in IMF-deposition in the yak. Additionally, LPL, ACADL, SCD, and FASN, which were previously shown to be associated with the IMF content, were identified in the competing endogenous RNA (ceRNA) regulatory network that was constructed on the basis of the IMF deposition-related genes. Three ceRNA subnetworks also revealed that TCONS-00016416 and its target SIRT1 “talk” to each other through the same miR-381-y and miR-208 response elements, whereas TCONS-00061798 and its target PRKCA, and TCONS-00084092 and its target LPL “talk” to each other through miR-122-x and miR-499-y response elements, respectively.

Conclusion

Taken together, our results reveal the potential mRNA and noncoding RNAs involved in IMF deposition in the yak, providing a useful resource for further research on IMF deposition in this animal species.

Cerasus humilis Cherry Polyphenol Reduces High-Fat Diet-Induced Obesity in C57BL/6 Mice by Mitigating Fat Deposition, Inflammation, and Oxidation

This study aimed to determine the anti-obesity effects and mechanisms of Cerasus humilis polyphenol (CHP) in C57BL/6 obese mice and 3T3-L1 cells. High-performance liquid chromatography-electrospray ionization-tandem mass spectrometry was used for the qualitative and quantitative identification of CHP components. The obese mice, induced by feeding high-fat diet (HFD), were treated with CHP (250 mg/kg/day) by gavage for 12 weeks. Orlistat was gavaged at 15.6 mg/kg bw/day, as a positive control group. The analysis revealed that the main components of CHP were procyanidin B2, cyanidin-3-glucoside, and pelargonidin-3-glucoside. CHP dietary supplementation significantly reduced body weight and improved blood lipid measurements in HFD-fed mice (p < 0.01). Moreover, it inhibited mRNA expression of miR-122, Srebp-1c, and Cpt1a (p < 0.01) and reduced hepatic lipid deposition, as seen by hematoxylin and eosin staining. CHP downregulated the protein expression of PPARγ and C/EBPα in HFD-induced obese mice and inhibited adipocyte differentiation (p < 0.01). Compared with the HFD group, CHP supplementation had an obvious anti-inflammatory effect (decreased protein expression, such as TNF-α, IL-6, and MCP1), reducing leptin levels and TNF-α secretion in serum and cells (p < 0.01). CHP significantly inhibited the expression of miR-27a/b (53.3 and 29.9%, p < 0.01) in mice retroperitoneal white adipocytes, enhancing the expression of the target gene Prdm16 and significantly upregulating Sirt1 (105.5%, p < 0.01) compared with the HFD group. Moreover, CHP supplementation effectively improved oxidative stress (ROS, T-AOC, SOD, CAT, and GSH-Px) induced by HFD in obese mice (p < 0.01). Thus, CHP mitigates adipocyte differentiation, browning of white adipocytes, and reduction of inflammation and antioxidant activity to reduce obesity. Consequently, these results provide novel insights into the anti-obesity roles of CHP in HFD-induced obesity.

Rice Bran Phenolic Extract Protects against Alcoholic Liver Injury in Mice by Alleviating Intestinal Microbiota Dysbiosis, Barrier Dysfunction, and Liver Inflammation Mediated by the Endotoxin-TLR4-NF-κB Pathway

Alcoholic liver injury, known as the most general result of chronic alcohol intake, is induced by inflammatory responses, which is activated by intestine-derived endotoxins formed from intestinal dysbiosis. The hepatoprotective activity of rice bran phenolic extract (RBPE) on ethanol-fed mice was investigated for the first time in this study, and the underlying mechanism was explored from gut microbiota, barrier function, and hepatic inflammation. Mice were fed an alcohol-containing liquid diet alone or in mixture with RBPE for 8 weeks. RBPE treatment mitigated ethanol-induced liver damage, evidenced by the declined lipid profile levels and hepatic function markers. Moreover, ethanol intake induced intestinal microbiota dysbiosis, which was attenuated by RBPE supplementation. RBPE treatment improved the alcohol-induced decrease in the expression of ZO-1, Claudin-1, Claudin-4, and Reg3g, revealing the ameliorative effect of RBPE on intestinal barrier dysfunction. Furthermore, RBPE treatment repressed the alcohol-induced trigger of the hepatic endotoxin-TLR4-NF-κB pathway, followed by the mitigated liver inflammation. The findings indicate that RBPE supplementation ameliorates intestinal microbiota dysbiosis and barrier dysfunction, inactivates the endotoxin-TLR4-NF-κB pathway, and represses inflammatory responses in liver, and therefore, intake of RBPE or brown rice may be an effective way to mitigate alcoholic liver injury.

miR-497 regulates fatty acid synthesis via LATS2 in bovine mammary epithelial cells

Both mRNA and miRNA play an important role in the regulation of mammary fatty acid metabolism and milk fat synthesis.

Comparison of the phenolic profiles and physicochemical properties of different varieties of thermally processed canned lychee pulp

Lychee pulp is rich in phenolics and has a variety of biological activities. However, the changes in the phenolic profile under heat treatment are unknown. The effect of the heat treatment temperature on commercial varieties (Guiwei and Nuomici) of canned lychee was investigated by comparing samples that were either unheated (UH), underwent 70 °C heat treatment (HT70) or underwent 121 °C heat treatment (HT121) and then were stored at room temperature. The results showed that the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of the UH, HT70 and HT121 samples were significantly decreased after storage at room temperature for 9 d, 13 d and 25 d, respectively. However, the TPC, TFC and antioxidant activity of HT121 canned lychee were still significantly higher than those of the UH and HT70 samples. However, the texture characteristics of the HT121 samples were worse than those of the UH and HT70 samples, and the color of the canned lychee was darker after the HT121 treatment. Nine individual phenolic compounds were detected in the canned lychee by HPLC-DAD. The gallic acid content was increased after HT121 treatment. In particular, (−)-gallocatechin was generated by HT121 thermal processing. However, after storage at room temperature for 9 d, the contents of (−)-gallocatechin in canned Guiwei and Nuomici were decreased by 96.27% and 94.04%, respectively, and (−)-gallocatechin disappeared after 25 d. In summary, the phenolic contents and antioxidant activity of canned lychee are increased by high-temperature treatment.

Lychee pulp is rich in phenolics and has a variety of biological activities.

Effects of Polyphenol-Rich Fruit Extracts on Diet-Induced Obesity in Rodents: Systematic Review and Meta-Analysis

Background::

Obesity is a complex condition of high prevalence and cost to the public health system. Recent research has demonstrated the potential of natural products, such as polyphenol-rich fruit extracts, for use in the treatment of obesity. The goal of this systematic review and meta-analysis is to determine the metabolic effects of polyphenol-rich fruit extracts on diet-induced obesity (DIO) in rodents.

Methods:

We searched MEDLINE, EMBASE, and Web of Science databases to identify preclinical studies that assessed polyphenol-rich fruit extracts compared to placebo on DIO in rodents in December 2018. Two researchers selected the studies, extracted the data, and assessed the quality of studies. Meta-analyses of standardized mean difference (SMD) of outcomes were calculated in Stata 11, and causes of heterogeneity were assessed by meta-regression.

Results:

We included 14 studies in the systematic review and 13 studies with 21 matched groups in the metaanalysis. Polyphenol-rich fruit extracts reduced the total body weight gain (SMD = -1.48; confidence interval: - 1.95, -1.01), energy intake (SMD = -0.42; -0.67, -0.17), visceral adipose tissue (SMD = -0.96; -1.25, -0.66), triglycerides (SMD = -1.00; -1.39, -0.62), cholesterol (SMD = -1.18, -1.66, -0.69), LDL- c (SMD = -1.15; -1.65, - 0.65), fasting glucose (SMD = -1.05; -1.65, -0.46), and fasting insulin (SMD = -1.40; -1.80, -1.00) when compared to vehicle.

Conclusion:

Polyphenol-rich fruit extract had positive effects on weight gain, dyslipidaemia, insulin resistance at different doses, and fruit source in male mice.

Lonicera caerulea Berry Polyphenols Activate SIRT1, Enhancing Inhibition of Raw264.7 Macrophage Foam Cell Formation and Promoting Cholesterol Efflux

Lonicera caerulea berry polyphenols (LCBP) are known to reduce cholesterol accumulation. Currently, it is unknown whether LCBP can activate Sirtuin 1 (SIRT1) to regulate the formation of RAW264.7 macrophage foam cells. In this study, the effect of LCBP on lipid accumulation in macrophages was evaluated. Fluorescently labeled ox-LDL and 25-NBD cholesterol were used to detect the ox-LDL uptake and cholesterol outflow rate from macrophages. Gene silencing was performed using siRNA to detect changes in the expression of the ATP-binding cassette transporter A1 (ABCA1), sterol regulatory element-binding protein 2 (SREBP2), and SIRT1 proteins using Western blotting, and changes in the expression of miR-33 were detected by real-time polymerase chain reaction. The results showed that treatment with 80 μg/mL LCBP significantly inhibited the accumulation of lipids in RAW264.7 macrophages induced by ox-LDL and reduced intracellular cholesterol levels by activating SIRT1 to enhance the expression of ABCA1, a cholesterol efflux gene, but not independent effect. Of the three key LCBP components investigated, chlorogenic acid was found to activate SIRT1 and regulate the expression of the cholesterol-related factors ABCA1, SREBP2, and miR-33; cyanidin-3-glucoside and catechins were effective to a lesser extent. Our results suggest a novel hypolipidemic mechanism of LCBP.

Impact of SchisandraChinensis Bee Pollen on Nonalcoholic Fatty Liver Disease and Gut Microbiota in HighFat Diet Induced Obese Mice

Schisandrachinensisbee pollen has been used as a health food in China for centuries; however, its bioactive constituents and functions are not very clear. In this study, we investigated the phenolic compounds of Schisandrachinensisbee pollen extract (SCPE) by UHPLC-Q-Orbitrap-HRMS/HPLC-DAD-ECD and its prevention from nonalcoholic fatty liver disease (NAFLD) and modulation of gut microbiota in high fat diet induced obese C57BL/6 mice. The results showed that 12 phenolic compounds were identified in SCPE, and naringenin, rutin and chrysin were the main constituents. The content of naringenin reached 1.89 mg/g, and total phenolic content (TPC) of SCPE were 101.83 mg GA/g. After obese mice were administrated with SCPE at 7.86 and 15.72 g/kg BW for 8 weeks, body weight gains were reduced by 18.23% and 19.37%. SCPE could decrease fasting blood glucose, cut down the lipid accumulation in serum and liver, lessen oxidative injury and inflammation in obesity mice. Moreover, SCPE could effectively inhibit the formation of NAFLD by inhibition of LXR-α, SREBP-1c and FAS genes expression, and modulate the structural alteration of gut microbiota in obesity mice. These findings suggested that SCPE could attenuate the features of the metabolism syndrome in obesity mice, which can be used to prevent obesity and NAFLD of human beings.

Polyphenols regulating microRNAs and inflammation biomarkers in obesity

Obesity is one of the most prevalent health problems worldwide. It is a complex disease that is generally accompanied by insulin resistance, increases in oxidative stress and inflammation biomarkers, and potentially, microRNA (miRNA) dysregulation. Polyphenols may act on obesity and its metabolic consequences. Circulating miRNAs have been studied as potential biomarkers for inflammatory and metabolic diseases, and their use may improve the diagnostic tools currently available and the ability to diagnose specific diseases. To our knowledge, data regarding the link between the consumption of polyphenols from food sources, miRNA expression, and inflammation biomarkers related to obesity is scarce, and most data available describing this relationship are found in cancer studies. This review focuses on the polyphenols that modulate the metabolism, inflammation, or both related to obesity to understand the extent to which miRNA expression can be modulated by dietary interventions.

Critical Roles of microRNAs in the Pathogenesis of Fatty Liver: New Advances, Challenges, and Potential Directions

In this review, we summarize the current understanding of microRNA (miRNA)-mediated modulation of the gene expression in the fatty liver as well as related signaling pathways. Because of the breadth and diversity of miRNAs, miRNAs may have a very wide variety of biological functions, and much evidence has confirmed that miRNAs are involved in the pathogenesis of fatty liver. In the pathophysiological mechanism of fatty liver, miRNAs may be regulated by upstream regulators, and have their own regulatory targets. miRNAs display important roles in the pathological mechanisms of alcoholic liver disease and non-alcoholic fatty liver disease. At present, most of the miRNA studies are focused on cell and tissue levels, and in vivo studies will help us elucidate the regulation of miRNAs and help us evaluate the potential of miRNAs as diagnostic markers and therapeutic targets. Furthermore, there is evidence that miRNAs are involved in the mechanism of natural medicine treatment in fatty liver. Given the important roles of miRNAs in the pathogenesis of fatty liver, we predict that studies of miRNAs in the pathogenesis of fatty liver will contribute to the elucidation of fatty liver pathology and the treatment of fatty liver patients.

The Potential and Action Mechanism of Polyphenols in the Treatment of Liver Diseases

Liver disease, involving a wide range of liver pathologies from fatty liver, hepatitis, and fibrosis to cirrhosis and hepatocellular carcinoma, is a serious health problem worldwide. In recent years, many natural foods and herbs with abundant phytochemicals have been proposed as health supplementation for patients with hepatic disorders. As an important category of phytochemicals, natural polyphenols have attracted increasing attention as potential agents for the prevention and treatment of liver diseases. The striking capacities in remitting oxidative stress, lipid metabolism, insulin resistance, and inflammation put polyphenols in the spotlight for the therapies of liver diseases. It has been reported that many polyphenols from a wide range of foods and herbs exert therapeutic effects on liver injuries via complicated mechanisms. Therefore, it is necessary to have a systematical review to sort out current researches to help better understand the potentials of polyphenols in liver diseases. In this review, we aim to summarize and update the existing evidence of natural polyphenols in the treatment of various liver diseases by in vitro, in vivo, and clinical studies, while special attention is paid to the action mechanisms.

Polysaccharide IV from Lycium barbarum L. Improves Lipid Profiles of Gestational Diabetes Mellitus of Pregnancy by Upregulating ABCA1 and Downregulating Sterol Regulatory Element-Binding Transcription 1 via miR-33

Lycium barbarum L. (LBL) has beneficial effects on gestational diabetes mellitus (GDM) but the related mechanism remains unclear. Polysaccharides of LBL (LBLP) are the main bioactive components of LBL. miR-33, ATP-binding cassette transporter A1 (ABCA1) and sterol regulatory element-binding transcription 1 (SREBF1) affect lipid profiles, which are associated with GDM risk. LBLP may exert protective against GDM by affecting these molecules. Four LBLP fractions: LBLP-I, LBLP-II, LBLP-III, and LBLP-IV were isolated from LBL and further purified by using DEAE-Sephadex column. The effects of purified each fraction on pancreatic beta cells were comparatively evaluated. A total of 158 GDM patients were recruited and randomly divided into LBL group (LG) and placebo group (CG). miR-33 levels, lipid profiles, insulin resistance and secretory functions were measured. The association between serum miR-33 levels and lipid profiles were evaluated by using Spearman's rank-order correlation test. After 4-week therapy, LBL reduced miR-33 level, insulin resistance and increased insulin secretion of GDM patients. LBL increased the levels of ABCA1, high-density lipoprotein cholesterol (HDL-C) and reduced miR-33, SREBF1, low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG), and malondialdehyde. Homeostatic model assessment of β-cell function and insulin resistance was lower in LG than in CG, whereas homeostatic model assessment of β-cell function and insulin secretory function was higher in LG than in CG. There was a strong positive association between miR-33 level and TG, or TC and or LDL-C, and a strong negative association between miR-33 level and HDL-C. The levels of miR-33 had negative relation with ABCA1 and positive relation with SREBF1. ABCA1 has negative relation with TG, TC, and LDL-C and positive relation with HDL-C. Inversely, SREBF1 had positive relation with TG, TC, and LDL-C and negative relation with HDL-C. The main bioactive compound LBLP-IV of LBL increased insulin secretion of beta cells and the levels of ABCA1, and reduced miR-33 levels and SREBF1 in beta cells. However, LBLP-IV could not change the levels of these molecules anymore when miR-33 was overexpressed or silenced. LBLP-IV had the similar effects with LBL on beta cells while other components had no such effects. Thus, LBLP-IV from LBL improves lipid profiles by upregulating ABCA1 and downregulating SREBF1 via miR-33.

Lychee (Litchi chinensis Sonn.) Pulp Phenolic Extract Provides Protection against Alcoholic Liver Injury in Mice by Alleviating Intestinal Microbiota Dysbiosis, Intestinal Barrier Dysfunction, and Liver Inflammation

Liver injury is the most common consequence of alcohol abuse, which is promoted by the inflammatory response triggered by gut-derived endotoxins produced as a consequence of intestinal microbiota dysbiosis and barrier dysfunction. The aim of this study was to investigate whether modulation of intestinal microbiota and barrier function, and liver inflammation contributes to the hepatoprotective effect of lychee pulp phenolic extract (LPPE) in alcohol-fed mice. Mice were treated with an ethanol-containing liquid diet alone or in combination with LPPE for 8 weeks. LPPE supplementation alleviated ethanol-induced liver injury and downregulated key markers of inflammation. Moreover, LPPE supplementation reversed the ethanol-induced alteration of intestinal microbiota composition and increased the expression of intestinal tight junction proteins, mucus protecting proteins, and antimicrobial proteins. Furthermore, in addition to decreasing serum endotoxin level, LPPE supplementation suppressed CD14 and toll-like receptor 4 expression, and repressed the activation of nuclear factor-κB p65 in the liver. These data suggest that intestinal microbiota dysbiosis, intestinal barrier dysfunction, and liver inflammation are improved by LPPE, and therefore, the intake of LPPE or Litchi pulp may be an effective strategy to alleviate the susceptibility to alcohol-induced hepatic diseases.

Optimized ultra-high-pressure-assisted extraction of procyanidins from lychee pericarp improves the antioxidant activity of extracts

To establish optimal ultra-high-pressure (UHP)-assisted extraction conditions for procyanidins from lychee pericarp, a response surface analysis method with four factors and three levels was adopted. The optimum conditions were as follows: 295 MPa pressure, 13 min pressure holding time, 16.0 mL/g liquid-to-solid ratio, and 70% ethanol concentration. Compared with conventional ethanol extraction and ultrasonic-assisted extraction methods, the yields of the total procyanidins, flavonoids, and phenolics extracted using the UHP process were significantly increased; consequently, the oxygen radical absorbance capacity and cellular antioxidant activity of UHP-assisted lychee pericarp extracts were substantially enhanced. LC-MS/MS and high-performance liquid chromatography quantification results for individual phenolic compounds revealed that the yield of procyanidin compounds, including epicatechin, procyanidin A2, and procyanidin B2, from lychee pericarp could be significantly improved by the UHP-assisted extraction process. This UHP-assisted extraction process is thus a practical method for the extraction of procyanidins from lychee pericarp.

Protective effect of crocin on BPA-induced liver toxicity in rats through inhibition of oxidative stress and downregulation of MAPK and MAPKAP signaling pathway and miRNA-122 expression

Bisphenol A (BPA) is an artificial environmental endocrine disrupting chemical and commonly used as a monomer of polycarbonate plastics and epoxy resins. The aim of the present study is to investigate the hepatoprotective effects of crocin, a constituent of saffron, against BPA-induced liver toxicity. We showed that treatment of male Wistar rats with 0.5 mg/kg BPA for 30 days increased the level of 8-isoprostane, decreased the level of reduced glutathione, elevated serum levels of aspartate aminotransferase, lactate dehydrogenase, triglyceride, and glucose, and induced periportal inflammation. Western blot results revealed that BPA increased the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK1/2), and mitogen-activated protein kinase-activated protein kinase (MAPKAPK), but not p38. BPA also reduced the Akt signaling activation and upregulated microRNA (miR-122) expression. Moreover, we showed here that crocin 20 mg/kg administration ameliorated liver damage and improved elevated levels of TG and liver enzymes of BPA-treated rats possibly though antioxidant activity, downregulation of miR-122 transcript level and lowering the phosphorylation of JNK, ERK1/2, and MAPKAPK and subsequently their activities. Overall, the findings suggest that crocin possesses hepatoprotective effects against BPA-induced liver toxicity by enhancing the antioxidative defense system and regulation of important signaling pathway activities and miR-122 expression.

Lychee (Litchi chinensis Sonn.) Pulp Phenolic Extract Confers a Protective Activity against Alcoholic Liver Disease in Mice by Alleviating Mitochondrial Dysfunction

Mitochondria play an important role in the initiation and development of alcoholic liver disease (ALD). Our previous studies found lychee pulp phenolic extract (LPPE) exerted protective effect against ALD partly by inhibiting fatty acid β-oxidation, and phenolic-rich lychee pulp extract improved restraint stress-induced liver injury by inhibiting mitochondrial dysfunction. The aim of this study was to investigate whether LPPE exerted protective effect against ALD via modulating mitochondrial function. The mice were treated with an ethanol-containing liquid diet alone or in combination with LPPE for 8 weeks. LPPE supplementation significantly alleviated hepatic steatosis, suppressed serum aspartate aminotransferase activity, and decreased triglyceride levels in serum and liver. On the basis of lipid peroxidation and antioxidant enzyme analyses, LPPE supplementation inhibited serum and hepatic oxidative stress. Moreover, LPPE supplementation significantly suppressed mitochondrial 8-hydroxy-2'-deoxyguanosine level, and increased mitochondrial membrane potential, mitochondrial DNA content, activities of mitochondrial complexes I and IV, and hepatic ATP level. Furthermore, LPPE supplementation significantly inhibited cytoplasmic cytochrome c level and caspase-3 activity, repressed Bax expression and Bax/Bcl-2 ratio, and increased Bcl-2 expression in liver. In summary, LPPE exerts beneficial effects against alcoholic liver injury by alleviating mitochondrial dysfunction.

Averrhoa carambolafree phenolic extract ameliorates nonalcoholic hepatic steatosis by modulating mircoRNA-34a, mircoRNA-33 and AMPK pathways in leptin receptor-deficient db/db mice

Averrhoa carambolafree phenolic extract ameliorates hepatic steatosis by modulating mircoRNA-34a, mircoRNA-33 and AMPK signaling.