Radix Stellariae extract prevents high-fat-diet-induced obesity in C57BL/6 mice by accelerating energy metabolism

The Anxiolytic Effect of Polysaccharides from Stellariae Radix through Monoamine Neurotransmitters, HPA Axis, and ECS/ERK/CREB/BDNF Signaling Pathway in Stress-induced Male Rats

BACKGROUND

Stellaria dichotoma L. var. lanceolata Bge. is renowned for its efficacy in "clearing deficiency heat" and represents a significant traditional Chinese medicine (TCM) resource. Modern pharmacology has demonstrated the anti-anxiety effects of Stellaria dichotoma L. var. lanceolata Bge. polysaccharides (SDPs). SDPs are one of the active constituents of Stellaria dichotoma L. var. lanceolata Bge. This study presents the first extraction of SDPs and investigates their potential molecular mechanisms and anxiolytic effects that are not previously reported.

METHODS

First, SDPs were obtained by water extraction and alcohol precipitation and analyzed for their monosaccharide composition by high performance liquid chromatography (HPLC). Male SD rats were subjected to a two-week indeterminate empty bottle stress procedure and a three-day acute restraint stress procedure, during which diazepam (DZP) (1 mg/kg) and SDPs (50, 100 and 200 mg/kg, intragastrically) were administered. A number of behavioral tests, including the elevated plus maze test (EPM), the open field test (OFT) and the light/dark box test (LDB), were used to assess the anti-anxiety potential of SDPs. Serum levels of Corticosterone (CORT) and Adrenocorticotropic hormone (ACTH), as well as the levels of Dopamine (DA) and serotonin (5-HT) found in the hippocampus and frontal cortex, were quantified using commercially available enzyme-linked immunosorbent assay (ELISA) kits. In addition, protein levels of key proteins cAMP-response element binding protein (CREB), phospho-CREB (p-CREB), brain-derived neurotrophic factor (BDNF), ERK½, p-ERK½, and GAPDH expression in rat hippocampus were measured by Western blot analysis, and modulation of the endocannabinoid system was assessed by immunohistochemistry.

RESULTS

Following administration of SDPs (50, 100, 200 mg/kg) and diazepam 1 mg/kg, anxiolytic activity was exhibited through an increase in the percentage of arm opening times and arm opening time of rats in the elevated plus maze. Additionally, there was an increase in the number of times and time spent in the open field center, percentage of time spent in the open box, and shuttle times in the LDB. Furthermore, tissue levels of DA and 5-HT were increased in the hippocampus and frontal cortex of rats after treatment with SDPs. In addition, SDPs significantly decreased serum levels of CORT and ACTH in rats. SDPs also effectively regulated the phosphorylation of the extracellular regulated protein kinases (ERK) and CREB-BDNF pathway in the hippocampus. Moreover, the expression levels of CB1 and CB2 proteins were heightened due to SDPs treatment in rats.

CONCLUSIONS

The study verified that SDPs alleviate anxiety in the EBS and ARS. The neuroregulatory behavior is accomplished by regulating the Monoamine neurotransmitter, HPA axis, and ECB-ERK-CREB-BDNF signaling pathway.

Protective effects of Radix Stellariae extract against Alzheimer's disease via autophagy activation in Caenorhabditis elegans and cellular models

Enhancing the clearance of proteins associated with Alzheimer's disease (AD) emerges as a promising approach for AD therapeutics. This study explores the potential of Radix Stellariae, a traditional Chinese medicine, in treating AD. Utilizing transgenic C. elegans models of AD, we demonstrated that a 75% ethanol extract of Radix Stellariae (RSE) (at 50 µg/mL) effectively diminishes Aβ and Tau protein expression, and alleviates their induced impairments including paralysis, behavioral dysfunction, neurotoxicity, and ROS accumulation. Additionally, RSE enhances the stress resistance of C. elegans. Further investigations revealed that RSE promotes autophagy, a critical cellular process for protein degradation, in these models. We found that inhibiting autophagy-related genes negated the neuroprotective effects of RSE, suggesting a central role for autophagy in the actions of RSE. In PC-12 cells, we observed that RSE not only inhibited Aβ fibril formation but also promoted the degradation of AD-related proteins and reduced their cytotoxicity. Mechanistically, RSE was found to induce autophagy via modulating PI3K/AKT/mTOR and AMPK/mTOR signaling pathways. Importantly, inhibiting autophagy counteracted the beneficial effects of RSE on the clearance of AD-associated proteins. Moreover, we identified Dichotomine B, a β-carboline alkaloid, as a key active constituent of RSE in mitigating AD pathology in C. elegans at concentrations ranging from 50 to 1000 µM. Collectively, our study presents novel discoveries that RSE alleviates AD pathology and toxicity primarily by inducing autophagy, both in vivo and in vitro. These findings open up new avenues for exploring the therapeutic potential of RSE and its active component, Dichotomine B, in treating neurodegenerative diseases like AD.

Allium macrostemon whole extract ameliorates obesity-induced inflammation and endoplasmic reticulum stress in adipose tissue of high-fat diet-fed C57BL/6N mice

Background

Obesity is a major risk factor for metabolic syndrome and a serious health concern worldwide. Various strategies exist to treat and prevent obesity, including dietary approaches using bioactive ingredients from natural sources.

Objective

This study aimed to investigate the anti-obesity effect of whole-plant Allium macrostemon (also called as long-stamen chive) extract (AME) as a potential new functional food.

Design

C57BL/6N mice were divided into three groups and fed either a control diet (CD), high-fat diet (HFD), or HFD with AME treatment (200 mg/kg BW daily) for 9 weeks. The mice in the CD and HFD groups were treated with vehicle control.

Results

AME supplementation reduced HFD-induced body weight gain, fat mass, and adipocyte size. AME suppressed peroxisome proliferator-activated receptor γ and fatty acid synthase mRNA expression, indicating reduced adipogenesis and lipogenesis in adipose tissue. In addition, AME lowered inflammation in adipose tissue, as demonstrated by the lower number of crown-like structures, mRNA, and/or protein expression of macrophage filtration markers, as well as pro-inflammatory cytokines, including F4/80 and IL-6. Endoplasmic reticulum stress was also alleviated by AME administration in adipose tissue. Several phenolic acids known to have anti-obesity effects, including ellagic acid, protocatechuic acid, and catechin, have been identified in AME.

Conclusion

By suppressing adipose tissue expansion and inflammation, AME is a potential functional food for the prevention and/or treatment of obesity and its complications.

Dichotomine B Attenuates Neuroinflammatory Responses by Regulating TLR4/MyD88-mTOR Signaling Pathway in BV2 Cells

Dichotomine B is a [Formula: see text]-Carboline alkaloid isolated from Stellariae Radix. Stellariae Radix, also known as Yin Chai Hu, is a common Chinese medicine in clinical practice. This herb has been demonstrated to have anti-inflammatory activity. This study aimed to investigate the effects and mechanisms of Dichotomine B on neuroinflammation by BV2 microglia induced by lipopolysaccharide (LPS) and adenosine triphosphate (ATP). The experiment was divided into a control group, a model group (10 µg/mL LPS + 5 mM ATP), a model+ TLR4 inhibitor (TAK-242, 10 µmol/L) group, model+ Dichotomine B (20, 40 and 80 µmol/L) groups and Dichotomine B (80 µmol/L) group. The BV2 cell viability was detected by MTT assay, the morphology of BV2 cells was observed by inverted microscope, and the levels of IL-6, IL-1[Formula: see text] and TNF-[Formula: see text] in BV2 cells were determined by ELISA. The expression levels of TLR4, MyD88, p-mTOR/mTOR, p62, p-RPS6/RPS6, LC3II/LC3I and Beclin-1 proteins were detected by western blot assay. The expression levels of TLR4, MyD88, mTOR, p62, RPS6, LC3B and Beclin-1 mRNA were detected by PCR assay. Finally, molecular docking was performed to predict the affinity of Dichotomine B with TLR4, MyD88 and mTOR by LibDock of Discovery Studio and MOE. The results showed that compared with the model group, the survival rates of damaged cells were significantly increased by TAK-242 and Dichotomine B, and the morphology of these BV2 cells improved. The levels of IL-6, IL-1[Formula: see text] and TNF-[Formula: see text] were significantly decreased by TAK-242 and Dichotomine B in LPS/ATP-induced BV2 cells. 80 µmol/L Dichotomine B has no effect on normal BV2 cells. Further mechanism investigation showed that TAK-242 and Dichotomine B significantly inhibited the protein and mRNA expression levels of TLR4, MyD88, p-mTOR/mTOR (mTOR), p62, p-RPS6/RPS6 (RPS6) and increased the protein and mRNA expression levels of LC3II/LC3I (LC3B), Beclin-1. Docking study showed the LibDock scores of Dichotomine B with TLR4, MyD88 and mTOR were all higher than those of positive drugs (Diazepam). These findings indicated that Dichotomine B attenuated neuroinflammatory responses in LPS/ATP-induced BV2 microglia, and its mechanism may be related to TLR4/MyD88-mTOR signaling pathway and autophagy.

Olanzapine-induced decreases of FGF21 in brown adipose tissue via histone modulations drive UCP1-dependent thermogenetic impairment

Long-term olanzapine treatment has been associated with serious metabolism disorders, such as abnormal body weight gain, hyperglycemia, and dyslipidemia. Recently, accumulated evidence points to a link between the metabolic disorders caused by olanzapine and thermogenetic impairment. Fibroblast growth factor 21 (FGF21), a pleiotropic protein, is a potent stimulator of thermogenesis in brown adipose tissue (BAT). However, the relationship between autocrine FGF21 in BAT and thermogenetic impairment induced by olanzapine has not been investigated. In this study, C57BL/6 mice and C3H10T1/2 (a brown adipocyte cell line) were used to investigate the role of FGF21 in modulating thermogenetic impairments caused by olanzapine. Our data found a fall in BAT temperature, with a decrease in the protein levels of uncoupling protein 1 (UCP1) and FGF21 in olanzapine-treatment mice. Olanzapine-induced deficits of mitochondrial activity and the expression of UCP1 and related thermogenetic factors could be improved by FGF21-overexpression in brown adipocytes. Furthermore, ChIP-sequencing showed the H3K9me3 modification in Fgf21 was dramatically increased in BAT of mice with olanzapine treatment. Lysine-specific demethylase 4a (KDM4a), a histone demethylase responsible for site-specific erasure of H3K9me3, was decreased in olanzapine-treated C3H10T1/2 cells, whereas FGF21 and UCP1 expression and thermogenesis were upregulated in KMD2a-overexpressing brown adipocyte. We concluded that FGF21 was a crucial regulator mediating UCP1-dependent thermogenetic impairments by olanzapine-modulating histone methylations. Our results also provide novel insights into identifying a new therapeutic target for treating metabolic side effects caused by the antipsychotic drug.

Evaluation of In Vitro Wound-Healing Potential, Antioxidant Capacity, and Antimicrobial Activity of Stellaria media (L.) Vill

The healing of skin wounds remains an important concern in medicine, especially in chronic wounds caused by various diseases such as diabetes. Using herbs or herbal products to heal skin wounds is a therapeutic challenge for traditional medicine. In this context, the main aim of our work was to highlight the in vitro healing potential of Stellaria media (L.) Vill. (SM) extract using the scratch assay on normal human dermal fibroblasts (NHDF). The ability to stimulate cell migration and proliferation under the influence of different concentrations of SM extract (range between 12.5 and 200 µg/mL) was determined compared to the control (untreated in vitro-simulated wound) and positive control (allantoin 50 µg/mL). Our results showed that the concentration of 100 µg/mL SM extract applied on the simulated wound recorded the strongest and fastest (24 h) migration (with wound closure) and proliferation of NHDF compared with the control. In addition, the SM extract was characterized in terms of bioactive compounds (total phenols and flavonoids content), antioxidant capacity (FRAP (The Ferric-Reducing Antioxidant Power) assay and electrochemical method), and antimicrobial activity. The results show that the SM extract contains a considerable amount of polyphenols (17.19 ± 1.32 mg GAE/g dw and 7.28 ± 1.18 mg QE/g dw for total phenol and flavonoid content, respectively) with antioxidant capacity. Antimicrobial activity against Gram-positive bacteria (S. aureus) is higher than E. coli at a dose of 15 µg/mL. This study showed that Stellaria media is a source of polyphenols compounds with antioxidant capacity, and for the first time, its wound healing potential was emphasized.

Stellaria media tea protects against diabetes-induced cardiac dysfunction in rats without affecting glucose tolerance

Background and aim

Common chickweed (Stellaria media) tea has traditionally been applied for treatment of various metabolic diseases including diabetes in folk medicine; however, experimental evidence to support this practice is lacking. Therefore, we aimed to assess the effect of Stellaria media tea on glucose homeostasis and cardiac performance in a rat model of diabetes.

Experimental procedure

Hot water extract of Stellaria media herb were analyzed and used in this study, where diabetes was induced by fructose-enriched diet supplemented with a single injection of streptozotocin. Half of the animals received Stellaria media tea (100 mg/kg) by oral gavage. At the end of the 20-week experimental period, blood samples were collected and isolated working heart perfusions were performed.

Results and conclusion

Compared to the animals receiving standard chow, serum fasting glucose level was increased and glucose tolerance was diminished in diabetic rats. Stellaria media tea did not affect significantly fasting hyperglycemia and glucose intolerance; however, it attenuated diabetes-induced deterioration of cardiac output and cardiac work. Analysis of the chemical composition of Stellaria media tea suggested the presence of rutin and various apigenin glycosides which have been reported to alleviate diabetic cardiomyopathy. Moreover, Stellaria media prevented diabetes-induced increase in cardiac STAT3 phosphorylation. We demonstrated for the first time that Stellaria media tea may beneficially affect cardiac dysfunction induced by diabetes without improvement of glucose homeostasis. Rutin and/or apigenin glycosides as well as modulation of STAT3 signaling may be implicated in the protection of Stellaria media tea against diabetic cardiomyopathy.

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Stellaria media (SM) tea attenuates diabetic deterioration of cardiac performance.

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SM tea contains apigenin glycosides and presumably rutin which have been reported to alleviate diabetic cardiomyopathy.

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SM tea restores diabetes-induced cardiac STAT3 phosphorylation.

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SM tea does not affect fasting hyperglycemia and glucose intolerance.

Effect of Sheng-Jiang Powder on Obesity-Induced Multiple Organ Injuries in Rats

Background and Aims

Obesity has become the main public health issue nowadays with poor control and has been associated with increased risk of multiorgan disease, but the specific mechanism and effective medication are still to be addressed. Sheng-jiang powder (SJP) showed great potential in preventing obesity in Chinese researches but has no trace in English reports. This study was designed to investigate the effect of SJP on obesity and obesity-mediated multiorgan injuries.

Methods

Rats were randomized into normal group (NG), obese group (OG), and SJP treatment group (SG). Obesity was induced by high-fat diet feeding. Rats were gavaged with SJP/normal saline daily from the third week and all rats were sacrificed after 12 weeks' feeding. Tissues were obtained for cytokines tests.

Results

Firstly, high-fat diet feeding led to significant obesity. Compared to NG, the level of SOD in the liver, spleen, lung, and kidney was much lower in OG (p < 0.05), while the pathological scores of pancreas, liver, spleen, lung, and kidney were much higher. SJP significantly increased SOD level in the liver, spleen, and lung and reduced the pathological scores of pancreas, liver, spleen, lung, and kidney correspondingly (p < 0.05).

Conclusions

SJP ameliorates inflammatory response and mitigates obesity-induced multiple organ injuries.