Schisandra polysaccharide increased glucose consumption by up-regulating the expression of GLUT-4

Optimization of Extraction Conditions for Water-Soluble Polysaccharides from the Roots of Adenophora tetraphylla (Thunb.) Fisch. and Its Effects on Glucose Consumption on HepG2 Cells

The root of Adenophora tetraphylla (Thunb.) Fisch. is a common Chinese materia medica and the polysaccharides which have been isolated from the plant are important active components for medicinal purposes. The objective of the current study was to optimize the extraction parameters and evaluate the glucose consumption activity for Adenophorae root polysaccharides (ARPs). The optimization of ARP extraction was evaluated with preliminary experiments and using response surface methodology (RSM). The conditions investigated were 35-45 °C extraction temperature, 20-30 (v/w) water-to-solid ratio, and 3-5 h extraction time. The antidiabetic effects of ARPs for the glucose consumption activity were evaluated in HepG2 cells. The statistical analyses of the experiments indicated that temperature, water-to-solid ratio, and extraction time significantly affected ARP yield (p < 0.01). The correlation analysis revealed that the experimental data were well-aligned with a quadratic polynomial model, as evidenced by the mathematical regression model's fit. The optimal conditions for maximum ARP yield were 45 °C extraction temperature and 28.47:1 (mL/g) water-to-solid ratio with a 4.60 h extraction time. Extracts from these conditions showed significant activity of promoting cell proliferation from 11.26% (p < 0.001) to 32.47% (p < 0.001) at a dose of 50 μg/mL to 800 μg/mL and increasing glucose consumption to 75.86% (p < 0.001) at 250 μg/mL on HepG2 cells. This study provides a sustainable alternative for the industry since it allowed simplified handling and a specific quantity of ARPs. Furthermore, ARPs might directly stimulate the glucose consumption in the liver and showed no cytotoxicity; therefore, ARPs probably could be taken as a potential natural source of antidiabetic materials.

Extraction, purification, structural characterization, and bioactivities of the genus Schisandra polysaccharides: A review

The genus Schisandra, a member of the Magnoliaceae family, is a well-known tonic traditional Chinese medicine with a long history of traditional medicinal and functional food used in China. Polysaccharides are one of its main active constituents, which have a wide range of bioactivities, such as anti-inflammatory, anti-tumor, neuroprotection, anti-diabetes, hepatoprotection, immunomodulation, and anti-fatigue. In this paper, we review the extraction, isolation, purification, structural characterization, bioactivities, as well as structure-activity relationship of polysaccharides from the genus Schisandra. In conclusion, we hope that this review could provide reference for the subsequent research on structural, bioactivities, development and application of the genus Schisandra polysaccharides.

Hepatoprotective effects of peach gum polysaccharides against alcoholic liver injury: moderation of oxidative stress and promotion of lipid metabolism

Natural polysaccharides extracted from plants have received increasing attention due to their rich bioactivity. In our study, peach gum polysaccharides (PGPs) were extracted by water extraction-alcohol precipitation method. PGPs are typical pyranose polysaccharides with a mean molecular weight of 3.68 × 106 g/mol. The antioxidant activity and hepatoprotective capacity of PGPs were studied. In vitro, assays showed that PGPs scavenged DPPH, OH, and O2- in a dose-dependent manner. PGPs exhibited antioxidative properties against alcohol-induced HL7702 cells, as evidenced by the normalization of MDA, SOD, ROS, and GSH levels. To further elucidate the hepatoprotective mechanism of PGPs, we carried out in vivo experiments in male mice. PGPs exerted hepatoprotective effects in alcohol liver disease (ALD) mice by exerting antioxidant effects, decreasing the inflammatory response and modulating lipid metabolism. In addition, metabolomic analysis indicated that PGPs mainly regulate D-glutamine and D-glutamate metabolism, alanine, aspartate and glutamate metabolism, and arginine biosynthesis to promote hepatic metabolism and maintain body functions. Overall, this study revealed that the hepatoprotective mechanism of PGPs against ALD might be associated with the regulation of oxidative stress and lipid metabolism.

Lipid-Lowering Effects of a Novel Polysaccharide Obtained from Fuzhuan Brick Tea In Vitro

Lipid accumulation causes diseases such as obesity and abnormal lipid metabolism, thus impairing human health. Tea polysaccharide is one of the natural, active substances that can lower lipid levels. In this paper, an oleic-acid-induced HepG2 cell model was established. The lipid-lowering effects of a novel group of Fuzhuan brick tea polysaccharides (FTPs)-obtained from Fuzhuan brick tea-were examined in vitro. The monosaccharide composition of FTP3 was Glc, Gal, Ara, Man, Rha, GalAc, GlcAc, and Xyl with a molar ratio of 23.5:13.2:9.0:5.5:5.4:2.7:1.3:1.0, respectively. A molecular weight of 335.68 kDa was identified for FTP3. HepG2 cells treated with FTP3 achieved a prominent lipid-lowering effect compared with cells treated with oleic acid. Images of the Oil Red O staining treatment showed that FTP3-treated groups had significantly fewer red fat droplets. TC and TG levels were lower in FTP3-treated groups. FTP3 alleviated lipid accumulation in HepG2 cells, activated AMPK, and decreased the SREBP-1C and FAS protein expressions associated with fatty acid synthesis. FTP3 holds promising potential for its lipid-lowering effects.

Polysaccharides from natural resource: ameliorate type 2 diabetes mellitus via regulation of oxidative stress network

Diabetes mellitus (DM) is a group of metabolic diseases characterized by hyperglycemia that can occur in children, adults, elderly people, and pregnant women. Oxidative stress is a significant adverse factor in the pathogenesis of DM, especially type 2 diabetes mellitus (T2DM), and metabolic syndrome. Natural polysaccharides are macromolecular compounds widely distributed in nature. Some polysaccharides derived from edible plants and microorganisms were reported as early as 10 years ago. However, the structural characterization of polysaccharides and their therapeutic mechanisms in diabetes are relatively shallow, limiting the application of polysaccharides. With further research, more natural polysaccharides have been reported to have antioxidant activity and therapeutic effects in diabetes, including plant polysaccharides, microbial polysaccharides, and polysaccharides from marine organisms and animals. Therefore, this paper summarizes the natural polysaccharides that have therapeutic potential for diabetes in the past 5 years, elucidating their pharmacological mechanisms and identified primary structures. It is expected to provide some reference for the application of polysaccharides, and provide a valuable resource for the development of new diabetic drugs.

Managing metabolic diseases: The roles and therapeutic prospects of herb-derived polysaccharides

Metabolic diseases have become a public health problem worldwide. Effective, novel and natural therapies are urgently needed to treat metabolic diseases. As natural bioactive compounds, polysaccharides have many physiological and medicinal properties. Recently, herb-derived polysaccharides have shown beneficial effects in the treatment of metabolic diseases, but the underlying mechanisms remain unclear. This review comprehensively summarizes the pharmacological progress and clinical evidence of herb-derived polysaccharides in the treatment of three metabolic diseases, namely type 2 diabetes mellitus, nonalcoholic fatty liver disease and obesity, and more importantly, discusses the molecular mechanism involved. Existing evidence has proved that herb-derived polysaccharides can maintain glucose homeostasis, promote insulin secretion, improve insulin resistance, reduce weight gain and hepatic steatosis, inhibit lipogenesis, alleviate oxidative stress and inflammation, and improve gut microbiota disorders in rodents with metabolic diseases. Notably, so far, human clinical trials of herb-derived polysaccharides for these three metabolic diseases remain rare. All in all, herb-derived polysaccharides may have good potential as drug candidates for the prevention and management of metabolic diseases. More high-quality clinical trials are needed to further validate its effectiveness and safety in human subjects.

The Therapeutic Potential of Plant Polysaccharides in Metabolic Diseases

Plant polysaccharides (PPS) composed of more than 10 monosaccharides show high safety and various pharmacological activities, including immunoregulatory, antitumor, antioxidative, antiaging, and other effects. In recent years, emerging evidence has indicated that many PPS are beneficial for metabolic diseases, such as cardiovascular disease (CVD), diabetes, obesity, and neurological diseases, which are usually caused by the metabolic disorder of fat, sugar, and protein. In this review, we introduce the common characteristics and functional activity of many representative PPS, emphasize the common risks and molecular mechanism of metabolic diseases, and discuss the pharmacological activity and mechanism of action of representative PPS obtained from plants including Aloe vera, Angelica sinensis, pumpkin, Lycium barbarum, Ginseng, Schisandra chinensis, Dioscorea pposite, Poria cocos, and tea in metabolic diseases. Finally, this review will provide directions and a reference for future research and for the development of PPS into potential drugs for the treatment of metabolic diseases.

Neohesperidin Dihydrochalcone Ameliorates High-Fat Diet-Induced Glycolipid Metabolism Disorder in Rats

High-fat diet (HFD) is closely related to the formation of metabolic diseases. Studies have confirmed that neohesperidin dihydrochalcone (NHDC) possesses the biological activity of preventing glycolipid metabolism disorder. To explore the mechanism of its preventive activity against glucolipid metabolism disorder, HFD-treated rats were orally administered with NHDC for 12 weeks continuously. The results showed that, compared with the HFD group, the intervention of 40-80 mg/kg body weight of NHDC effectively downregulated the level of fasting blood glucose. Western blot analysis revealed that the treatment of NHDC alleviated the inhibitory effect of HFD on the expression of hepatic GLUT-4 and IRS-1. Further studies confirmed that NHDC reduced the degree of HFD-stimulated inflammation of ileum through the TLR4/MyD88/NF-κB signaling pathway. Moreover, ileum intestinal flora analysis showed that intragastric administration of NHDC reversed the change of Proteobacteria abundance and the Firmicutes/Bacteroidetes (F/B) ratio caused by HFD. At the generic level, NHDC promoted the relative abundance of Coprococcus, Bifidobacterium, Clostridium, Oscillospira, and [Eubacterium], while reducing the relative abundance of Defluviitalea and Prevotella. Taken together, these findings suggest that NHDC possesses the biological activity of improving HFD-induced glycolipid metabolism disorder.

Efficacy and Safety of Omija (Schisandra chinensis) Extract Mixture on the Improvement of Hyperglycemia: A Randomized, Double-Blind, and Placebo-Controlled Clinical Trial

A previous animal study demonstrated that the administration of Omija extract and soybean mixture (OSM) improved glycemic control in the type 2 diabetes model. In this study, we conducted a 12-week, randomized, double-blinded, and placebo-controlled clinical trial to determine the effects of OSM in humans with hyperglycemia. Participants with fasting plasma concentrations of 100–140 mg/dL were enrolled (n = 80) and administered either OSM or placebo products for 12 weeks. The outcomes included measurements of efficacy (fasting plasma glucose (FPG), postprandial glucose (PPG), fasting plasma insulin (FPI), postprandial insulin (PPI), hemoglobin A1c (HbA1c), C-peptide, fructosamine, and lipid parameters) and safety at baseline and at 12 weeks. After the intervention, the OSM group showed significantly decreased levels of FPG, PPG (30, 60 min), PPI (60 min), insulin area under the curve (AUC), fructosamine, and low-density-lipoprotein (LDL) cholesterol compared to the placebo group. No clinically significant changes in any safety parameter were observed. Therefore, it is hypothesized that OSM supplementation is an effective and safe functional food supplement for humans with hyperglycemia.

Lipid-Lowering Effects of Inonotus obliquus Polysaccharide In Vivo and In Vitro

Excessive lipid intake will cause hyperlipidemia, fatty liver metabolism disease, and endanger people’s health. Edible fungus polysaccharide is a natural active substance for lipid lowering. In this study, the HepG2 cell model induced by oleic acid and mice model induced by a high-fat diet was established. The lipid-lowering effects of Inonotus obliquus polysaccharide (IOP) was investigated in vivo and in vitro. Glucose (251.33 mg/g), rhamnose (11.53 mg/g), ribose (5.10 mg/g), glucuronic acid (6.30 mg/g), and galacturonic acid (2.95 mg/g) are present in IOP, at a ratio of 85.2:3.91:1.73:2.14:1. The molecular weight of IOP is 42.28 kDa. Treatment with 60 mg/L of IOP showed a significant lipid-lowering effect in HepG2 cells compared with the oleic acid-treated group. In the oil red O-stained images, the red fat droplets in the IOP-treated groups were significantly reduced. TC and TG levels of IOP-treated groups decreased. IOP can alleviate the lipid deposition in the mice liver due to high-fat diet, and significantly reduce their serum TC, TG, and LDL-C contents. IOP could activate AMPK but decrease the SREBP-1C, FAS, and ACC protein expression related to adipose synthesis in mice. IOP has a certain potential for lipid-lowering effects both in vivo and in vitro.

Efficacy and safety of Shenqi Jiangtang Granules plus oral hypoglycemic agent in patients with type 2 diabetes mellitus: A protocol for systematic review and meta-analysis of 15 RCTs

OBJECTIVE

Shenqi Jiangtang Granules (SQJTG) has been widely used to treat patients with type 2 diabetes mellitus (T2DM). But whether there exists sufficient evidence on the efficacy of SQJTG in the treatment of T2DM is unclear. In order to assess the effects of SQJTG for T2DM, a systematic review and meta-analysis of randomized controlled trials (RCTs) were carried out.

METHODS

Eight databases, namely, PubMed, The Cochrane Library, EMBASE, Web of Science, Chinese National Knowledge Infrastructure, Chinese Scientific Journals Full-Text Database, CBM, and Wanfang database were searched up to May 2020. According to the Cochrane standards, the selection of study, the extraction of data, the assessment of study quality, and the analyses of data were carried out strictly. Then a fixed or random effects model was applied to analyze the outcomes.

RESULTS

Fifteen studies (N = 1392) in total conformed the inclusion criteria to this meta-analysis. Two subgroups were identified, based on different dose of SQJTG: oral hypoglycemic agent (OHA) vs OHA plus SQJTG (1 g); OHA vs. OHA plus SQJTG (1.5-3 g). The pooled results showed that, in comparison with OHA, OHA plus SQJTG significantly reduced fasting plasma glucose in both 1 g subgroup and 1.5-3 g subgroup; 2-hour post-meal blood glucose was also greatly reduced in the SQJTG 1 g subgroup and the SQJTG 1.5-3 g subgroup. Compared with OHA, SQJTG 1 g subgroup significantly reduced levels of glycated hemoglobin A1c, as well as the SQJTG 1.5-3 g subgroup. Homeostasis model-insulin resistance index was also reduced in both SQJTG 1 g subgroup and SQJTG 1.5-3 g subgroup; SQJTG group can also significantly reduce the total adverse events especially in reducing the incidence of hypoglycemia.

CONCLUSIONS

SQJTG is an effective and safe complementary treatment for T2DM patients. This meta-analysis provides an evidence for the treatment in patients with T2DM. While owing to the high heterogeneity and the trials' small sample size, it's crucial to perform large-scale and strict designed studies.

Novel Protein Tyrosine Phosphatase 1B Inhibitor-Geranylated Flavonoid from Mulberry Leaves Ameliorates Insulin Resistance

Mulberry leaf is a common vegetable with a variety of beneficial effects, such as hypoglycemic activity. However, the underlying mechanism of its hypoglycemic effect have not been fully revealed. In this study, two flavonoid derivatives were isolated from mulberry leaves, a new geranylated flavonoid compound (1) and its structural analogue (2). The structures of compounds 1 and 2 were elucidated using spectroscopic analysis. To study the potential hypoglycemic properties of these compounds, their regulatory effects on protein tyrosine phosphatase 1B (PTP1B) were investigated. In comparison to oleanolic acid, compounds 1 and 2 showed significant inhibitory activities (IC₅₀ = 4.53 ± 0.31 and 10.53 ± 1.76 μM) against PTP1B, the positive control (IC₅₀ = 7.94 ± 0.76 μM). Molecular docking predicted the binding sites of compound 1 to PTP1B. In insulin-resistance HepG2 cell, compound 1 promoted glucose consumption in a dose-dependent manner. Furthermore, western blot and polymerase chain reaction analyses indicated that compound 1 might regulate glucose consumption through the PTP1B/IRS/PI3K/AKT pathway. In conclusion, geranylated flavonoids in mulberry leaves inhibite PTP1B and increase the glucose consumption in insulin-resistant cells. These findings provide an important basis for the use of mulberry leaf flavonoids as a dietary supplement to regulate glucose metabolism.

Schisandra Chinensis Acidic Polysaccharide Improves the Insulin Resistance in Type 2 Diabetic Rats by Inhibiting Inflammation

Polysaccharide from Schisandra chinensis has the effect of lowering blood glucose and improving insulin resistance (IR). However, its underlying mechanism remains unclear. In this study, a rat model of type 2 diabetes (T2D) was created to explore whether S. chinensis acidic polysaccharide (SCAP) would improve the IR in T2D rats by inhibiting inflammation. A combination of a high-fat diet and low dose of streptozotocin (STZ, 30 mg/kg, intraperitoneally) were administered to rats for establishing the T2D model. Then, these T2D rats were orally administered with SCAP (25, 50, or 100 mg/kg) for 8 weeks. The results indicated that SCAP significantly lowered the fasting blood glucose, elevated the fasting insulin, and improved glucose tolerance. SCAP also decreased the serum interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and nuclear factor-κB (NF-κB) levels, as well as their mRNA expression in the liver tissue. Further, SCAP significantly inhibited the upregulation of phosphorylated c-Jun N-terminal kinase (p-JNK) and NF-κB protein, and it increased phosphorylated insulin receptor substrate-1 (p-IRS-1), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), and phosphorylated protein kinase B (p-AKT) protein expression levels significantly. These results suggest that SCAP improves the IR in T2D rats by inhibiting inflammation.

Potential correlation between carbohydrate-active enzyme family 48 expressed by gut microbiota and the expression of intestinal epithelial AMP-activated protein kinase β

The expression of the carbohydrate-active enzyme family and related genes is known to be influenced by the response of intestinal microbiota to dietary changes. However, it is uncertain whether this is caused by variation in the intestinal microecology. In this study, metabolite analysis, 16S rDNA sequencing, metagenomics, and Western blotting were employed to investigate the effects of dietary intervention on the composition of gut microbiota and microbiota-mediated changes. The results showed that compared with the low fiber-fed group, the fiber diet-fed mice displayed a shift in gut microbiota composition to contain more members of phylum Bacteroidetes, accompanied by higher proportions of Akkermansia and typical probiotic Bifidobacterium. Moreover, correlations were found between microbial genes coding for carbohydrate-binding module family 48 (CBM48) and intestinal epithelial expression levels of AMPK β. This finding provides new insight for elucidating the contribution of dietary intervention through AMPK regulation linked to the microbial carbohydrate-binding family. PRACTICAL APPLICATIONS: The relationship suggested by these data will provide theoretical and applied foundations for the development of potential intervention targeting the interaction between gut microbiota and host health, particularly the use of dietary fiber as a medically relevant food. Additionally, a better understanding of the interactions between gut microbiota and intestinal epithelial will inform the development of gut microbiota intervention as a health-promoting procedure.

Potential of Schisandra chinensis (Turcz.) Baill. in Human Health and Nutrition: A Review of Current Knowledge and Therapeutic Perspectives

Schisandra chinensis (Turcz.) Baill. (SCE) is a plant with high potential for beneficial health effects, confirmed by molecular studies. Its constituents exert anti-cancer effects through the induction of cell cycle arrest and apoptosis, as well as inhibition of invasion and metastasis in cancer cell lines and experimental animals. SCE displays antimicrobial effects against several pathogenic strains. It has anti-diabetic potential, supported by hypoglycemic activity. A diet rich in SCE improves pancreatic functions, stimulates insulin secretion, and reduces complications in diabetic animals. SCE prevents lipid accumulation and differentiation of preadipocytes, indicating its anti-obesity potential. SCE exerts a protective effect against skin photoaging, osteoarthritis, sarcopenia, senescence, and mitochondrial dysfunction, and improves physical endurance and cognitive/behavioural functions, which can be linked with its general anti-aging potency. In food technology, SCE is applied as a preservative, and as an additive to increase the flavour, taste, and nutritional value of food. In summary, SCE displays a variety of beneficial health effects, with no side effects. Further research is needed to determine the molecular mechanisms of SCE action. First, the constituents responsible for its beneficial effects should be isolated and identified, and recommended as preventative nutritional additives, or considered as therapeutics.

Effects of Vaspin on Insulin Resistance in Rats and Underlying Mechanisms

Insulin resistance (IR) is the main pathogenesis of metabolic syndrome and a shared pathophysiological change in conditions such as diabetes mellitus, adiposity, hypertension, and atherosclerosis. Visceral adipose tissue-derived serpin (Vaspin) is a newly discovered adipocytokine with insulin-sensitizing and anti-inflammatory effects. To examine if vaspin can improve insulin resistance in rats fed a high-fat diet via the insulin receptor substrate/phosphatidylinositol 3 kinase/protein kinase B/glucose transport (IRS/PI3K/Akt/Glut) and inhibitory κB alpha/nuclear factor-kappa B (IκBα/NF-κB) signalling pathways, thirty male Sprague-Dawley (SD) rats were randomly divided into three groups: the normal control group (NC group, n = 10), high-fat diet group (HFD group, n = 10) and vaspin intervention group (HFD + vaspin group, n = 10). Results showed that intervention with vaspin significantly decreased fasting blood glucose (FBG) and fasting insulin (FINS) concentrations in HFD − fed rats without significantly affecting body weight or triglyceride (TG) or total cholesterol (TC) levels. The areas under the intraperitoneal glucose tolerance test (IPGTT) and the insulin tolerance test (ITT) curves were significantly decreased in HFD + vaspin group compared with the HFD group, and the glucose infusion rate (GIR) showed the same trends. Western blot, real-time polymerase chain reaction (RT-PCR) and immunofluorescence staining showed that vaspin could improve insulin resistance in liver, skeletal muscle and adipose tissue by activating the IRS/PI3K/Akt/Glut signalling pathway and inhibiting the IκBα/NF-κB signalling pathway.

Dual-functional Brij-S20-modified nanocrystal formulation enhances the intestinal transport and oral bioavailability of berberine

Introduction

Berberine (BBR) is a plant-derived benzylisoquinoline alkaloid and has been demonstrated to be a potential treatment for various chronic diseases. The poor water solubility and P-glycoprotein (Pgp)-mediated drug efflux are the main challenges for its further application in a clinical setting.

Materials and methods

In this study, a Brij-S20 (BS20)-modified nanocrystal formulation (BBR-BS20-NCs) has been developed and investigated with the purpose of improving the intestinal absorption of BBR. The physicochemical properties of the developed BBR-BS20-NCs were characterized and the enhancement of the BBR-BS20-NCs on BBR absorption were investigated both in vitro and in vivo.

Results

The results indicated that BS20 could significantly enhance the intracellular uptake of BBR in MDCK-MDR1 cells via a short-term and reversible modulation on the Pgp function, accompanied by a marked increase in Pgp mRNA expression but without significant influence on the Pgp protein expression. Moreover, the morphology of the prepared BBR-BS20-NCs was observed to be prism-like, with a smooth surface and an average diameter of 148.0 ± 3.2 nm. Compared to raw BBR and physical mixture, BBR-BS20-NCs facilitated the dissolution rate and extent of release of BBR in aqueous solution, and further increased the absorption of BBR in MDCK-MDR1 monolayer by overcoming the Pgp-mediated secretory transport (P_app[BL-AP] values of 2.85 ± 0.04 × 10⁻⁶ cm/s, 2.21 ± 0.14 × 10⁻⁶ cm/s, and 2.00 ± 0.07 × 10⁻⁶ cm/s for pure BBR, physical mixture, and BBR-BS20-NCs, respectively). Significant improvements in the maximum concentration observed (C_max) and area under drug concentration-time curve (AUC_0–t) of BBR-BS20-NCs were obtained in pharmacokinetic studies compared to pure BBR, and the relative bioavailability of BBR-BS20-NCs to pure BBR was 404.1%.

Conclusion

The developed BBR-BS20-NCs combine the advantages of nanocrystal formulation and functional excipient. The novel pharmaceutical design provides a new strategy to improve the oral bioavailability of those drugs with both poor water solubility and Pgp-mediated efflux.

Erythropoietin and mTOR: A "One-Two Punch" for Aging-Related Disorders Accompanied by Enhanced Life Expectancy

Life expectancy continues to increase throughout the world, but is accompanied by a rise in the incidence of non-communicable diseases. As a result, the benefits of an increased lifespan can be limited by aging-related disorders that necessitate new directives for the development of effective and safe treatment modalities. With this objective, the mechanistic target of rapamycin (mTOR), a 289-kDa serine/threonine protein, and its related pathways of mTOR Complex 1 (mTORC1), mTOR Complex 2 (mTORC2), proline rich Akt substrate 40 kDa (PRAS40), AMP activated protein kinase (AMPK), Wnt signaling, and silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), have generated significant excitement for furthering novel therapies applicable to multiple systems of the body. Yet, the biological and clinical outcome of these pathways can be complex especially with oversight of cell death mechanisms that involve apoptosis and autophagy. Growth factors, and in particular erythropoietin (EPO), are one avenue under consideration to implement control over cell death pathways since EPO can offer potential treatment for multiple disease entities and is intimately dependent upon mTOR signaling. In experimental and clinical studies, EPO appears to have significant efficacy in treating several disorders including those involving the developing brain. However, in mature populations that are affected by aging-related disorders, the direction for the use of EPO to treat clinical disease is less clear that may be dependent upon a number of factors including the understanding of mTOR signaling. Continued focus upon the regulatory elements that control EPO and mTOR signaling could generate critical insights for targeting a broad range of clinical maladies.

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice

Objectives

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice.

Methods

Mice were given DNLA at doses of 10–80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis.

Key findings

Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα.

Conclusions

DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders.

Yixinshu ameliorates hippocampus abnormality induced by heart failureviathe PPARγ signaling pathway

Yizinshu (YXS) improves cardiac function and ameliorates hippocampus abnormality induced by heart failureviathe PPARγ signaling pathway.

Wuweizi protects against liver cirrhosis by promoting endogenous stem cell proliferation

AIM: To investigate the mechanism for Wuweizi to treat liver cirrhosis.

METHODS: A rat model of liver cirrhosis was developed with CCl₄. Rats were randomly divided into five groups: three treatment groups [small dose Wuweizi group (A1), middle dose group (A2) and high dose group (A3)], a blank group (C) and a model group (M). Except group C, liver cirrhosis was induced in all other groups. Groups A1, A2 and A3 were given 1.0, 1.5 and 2.0 mg/200 g Wuweizi, respectively. After treatment, histopathology, liver function [aspartate transaminase (AST), alanine transaminase (ALT) and albumin (ALB)], hepatic fibrosis, stem cell proliferation, and the expression ofCK-18, ALB and α-fetoprotein (AFP) were assessed.

RESULTS: In the treatment groups, there was an improvement in the degree of hepatic fibrosis and the condition of liver cell degeneration and necrosis, as revealed by HE staining and Masson staining, and the liver fibrosis scores were different among each treatment group (P < 0.05). Compared with group M, the liver fibrosis score of group A2 was improved most obviously (P < 0.01). Immunohistochemistry analysis showed that the expression of CK-18, ALB and AFP was different between each treatment group (P < 0.05). By labeling liver tissue stem cells with BrdU, the proliferation and division of stem cells were observed through the method of "regional coexistence". Immunofluorescence analysis revealed that the expression of CK-18, ALB and AFP were different among each treatment group (P < 0.01), with group A2 having the most prominent expression (P < 0.01). Liver function was improved differently in each treatment group (P < 0.05). Compared with group M, AST and ALT were decreased most significantly and ALB increased most obviously in group A2 (P < 0.01).

CONCLUSION: Wuweizi has a protective effect on injured liver cells. Wuweizi could delay the process of liver cirrhosis via mechanisms possibly related to promoting the proliferation of endogenous stem cells.