Novel anti-obesity effect of scutellarein and potential underlying mechanism of actions

Review on the pharmacological effects and pharmacokinetics of scutellarein

Scutellarein is a flavonoid from Scutellaria baicalensis  Georgi that has been shown to have a variety of pharmacological activities. This review aims to summarize the pharmacological and pharmacokinetic studies on scutellarein and provide useful information for relevant scholars. Pharmacological studies indicate that scutellarein possesses a diverse range of pharmacological properties, including but not limited to anti-inflammatory, antioxidant, antiviral, neuroprotective, hypoglycemic, hypolipidemic, anticancer, and cardiovascular protective effects. Further investigation reveals that the pharmacological effects of scutellarein are driven by multiple mechanisms. These mechanisms encompass the scavenging of free radicals, inhibition of the activation of inflammatory signaling pathways and expression of inflammatory mediators, inhibition of the activity of crucial viral proteins, suppression of gluconeogenesis, amelioration of insulin resistance, improvement of cerebral ischemia-reperfusion injury, induction of apoptosis in cancer cells, and prevention of myocardial hypertrophy, among others. In summary, these pharmacological studies suggest that scutellarein holds promise for the treatment of various diseases. It is imperative to conduct clinical studies to further elucidate the therapeutic effects of scutellarein. However, it is worth noting that studies on the pharmacokinetics reveal an inhibitory effect of scutellarein on uridine 5'-diphosphate glucuronide transferases and cytochrome P450 enzymes, potentially posing safety risks.

Food therapy of scutellarein ameliorates pirarubicin‑induced cardiotoxicity in rats by inhibiting apoptosis and ferroptosis through regulation of NOX2‑induced oxidative stress

Pirarubicin (THP) is one of the most commonly used antineoplastic drugs in clinical practice. However, its clinical application is limited due to its toxic and heart‑related side effects. It has been reported that oxidative stress, inflammation and apoptosis are closely associated with cardiotoxicity caused by pirarubicin (CTP). Additionally, it has also been reported that scutellarein (Sc) exerts anti‑inflammatory, antioxidant, cardio‑cerebral vascular protective and anti‑apoptotic properties. Therefore, the present study aimed to investigate the effect of food therapy with Sc on CTP and its underlying molecular mechanism using echocardiography, immunofluorescence, western blot, ROS staining, and TUNEL staining. The in vivo results demonstrated that THP was associated with cardiotoxicity. Additionally, abnormal changes in the expression of indicators associated with oxidative stress, ferroptosis and apoptosis were observed, which were restored by Sc. Therefore, it was hypothesized that CTP could be associated with oxidative stress, ferroptosis and apoptosis. Furthermore, the in vitro experiments showed that Sc and the NADPH oxidase 2 (NOX2) inhibitor, GSK2795039 (GSK), upregulated glutathione peroxidase 4 (GPX4) and inhibited THP‑induced oxidative stress, apoptosis and ferroptosis. However, cell treatment with the ferroptosis inhibitor, ferrostatin‑1, or inducer, erastin, could not significantly reduce or promote, respectively, the expression of NOX2. However, GSK significantly affected ferroptosis and GPX4 expression. Overall, the results of the present study indicated that food therapy with Sc ameliorated CTP via inhibition of apoptosis and ferroptosis through regulation of NOX2‑induced oxidative stress, thus suggesting that Sc may be a potential therapeutic drug against CTP.

A sport supplement candidate of Erigeron breviscapus extract regulates lipogenesis in vitro and in vivo

PURPOSE

One of the urgent research projects in exercise science should focus on sports supplements for obese people who lack exercise and physical activity. In this study, we explored the efficacy in non-alcoholic fatty liver disease (NAFLD) mice models using a Korean herbal medicine Erigeron breviscapus (EB).

METHODS

Gene ontology analyses of active compounds in EB were performed using the Traditional Chinese Medicine Database and Analysis Platform (TCMSP) and Cytoscape program, respectively. PA-induced acid (PA) induced-lipid droplets in HepG2 cells were analyzed using a 3D-hologram. To analyze the fat-suppressing efficacy of EB in animal experiments, NAFLD was induced through a 24-week high-fat diet. Subsequently, the same diet was continued for an additional 8 weeks, with concurrent co-administration of drugs for efficacy analysis. In the 8-week experiment, mice were administered saline alone, metformin (17 mg/kg/day), or EB (26 mg/kg/day). The mice were sacrificed and the liver tissue was isolated. The liver tissues were stained with H&E and specific antibodies such as sterol regulatory element binding protein 1 (SREBP-1) and peroxisome proliferator-activated receptor- γ (PPAR-γ).

RESULTS

Seventeen EB-active compounds were identified by whole-body analysis. EB downregulated lipid droplets in PA-treated HepG2 cells. EB regulates lipid accumulation in liver tissue of HFD-fed NAFLD mice Metformin and EB significantly reduced the expression of SREBP-1 and PPAR-γ in liver tissue.

CONCLUSION

We suggest that EB is a candidate for the management of NAFLD and is an effective exercise supplement owing to its ability to inhibit lipid accumulation.

Engineered production of bioactive polyphenolic O-glycosides

Polyphenolic compounds (such as quercetin and resveratrol) possess potential medicinal values due to their various bioactivities, but poor water solubility hinders their health benefits to humankind. Glycosylation is a well-known post-modification method to biosynthesize natural product glycosides with improved hydrophilicity. Glycosylation has profound effects on decreasing toxicity, increasing bioavailability and stability, together with changing bioactivity of polyphenolic compounds. Therefore, polyphenolic glycosides can be used as food additives, therapeutics, and nutraceuticals. Engineered biosynthesis provides an environmentally friendly and cost-effective approach to generate polyphenolic glycosides through the use of various glycosyltransferases (GTs) and sugar biosynthetic enzymes. GTs transfer the sugar moieties from nucleotide-activated diphosphate sugar (NDP-sugar) donors to sugar acceptors such as polyphenolic compounds. In this review, we systematically review and summarize the representative polyphenolic O-glycosides with various bioactivities and their engineered biosynthesis in microbes with different biotechnological strategies. We also review the major routes towards NDP-sugar formation in microbes, which is significant for producing unusual or novel glycosides. Finally, we discuss the trends in NDP-sugar based glycosylation research to promote the development of prodrugs that positively impact human health and wellness.

Network Pharmacological Analysis of a New Herbal Combination Targeting Hyperlipidemia and Efficacy Validation In Vitro

The network pharmacology (NP) approach is a valuable novel methodology for understanding the complex pharmacological mechanisms of medicinal herbs. In addition, various in silico analysis techniques combined with the NP can improve the understanding of various issues used in natural product research. This study assessed the therapeutic effects of Arum ternata (AT), Poria cocos (PC), and Zingiber officinale (ZO) on hyperlipidemia after network pharmacologic analysis. A protein-protein interaction (PPI) network of forty-one key targets was analyzed to discover core functional clusters of the herbal compounds. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and gene ontology (GO) term enrichment analysis identified significant categories of hypolipidemic mechanisms. The STITCH database indicated a high connection with several statin drugs, deduced by the similarity in targets. AT, PC, and ZO regulated the genes related to the energy metabolism and lipogenesis in HepG2 cells loaded with free fatty acids (FFAs). Furthermore, the mixture of three herbs had a combinational effect. The herbal combination exerted superior efficacy compared to a single herb, particularly in regulating acetyl-CoA carboxylase (ACC) and carnitine palmitoyltransferase 1 (CPT-1). In conclusion, the network pharmacologic approach was used to assess potential targets of the herbal combination for treatment. Experimental data from FFA-induced HepG2 cells suggested that the combination of AT, PC, and ZO might attenuate hyperlipidemia and its associated hepatic steatosis.

Anti-obesity effect of Angelica keiskei Jiaosu prepared by yeast fermentation on high-fat diet-fed mice

In this study, an Angelica keiskei (A. keiskei) Jiaosu (FAK) was prepared by yeast fermentation to investigate its anti-obesity effect on high-fat diet (HFD)-fed mice. 70 SPF grade male C57BL/6J mice were randomly divided into 7 groups (n = 10): blank control group (N), high-fat model group (M), positive control group (Orl), unfermented control group (NF), high-dose intervention group (FH), medium-dose intervention group (FM), and low-dose intervention group (FL). The results showed that FAK intervention significantly reduced the body weight, Lee's index and liver index of HFD-fed mice (P < 0.05). Compared with M group, the serum levels of triglyceride (TG), total cholesterol (TC), leptin and glucose (GLU) in FH group were remarkably decreased and that of interleukin-27 (IL-27) were increased (P < 0.05). The levels of TG, and TC in the liver of mice were also markedly decreased in the FH group (P < 0.05). HE staining results showed that the liver cells in the three intervention groups had less degeneration and fatty vacuoles in the cytoplasm, and the liver cords were orderly arranged compared with that of M group. Furthermore, FAK significantly inhibited epididymal adipose tissue cell expansion induced by HFD. FAK up-regulated the protein expression levels of p-AMPK and PPARα to promote lipolysis and down-regulated the expression of PPARγ to reduce lipid synthesis (P < 0.05). Additionally, the results of gut microbiota showed that after the intervention, a decrease trend of F/B value and Deferribacterota was noticed in the FH group compared with M group. At the genus level, FAK intervention significantly increased that of Ileiobacterium compared to the M group (p < 0.05). A rising trend of norank_f_Muribaculaceae, Lactobacillus, and Bifidobacterium were also observed in the HF group. Conclusively, these findings demonstrated that FAK intervention can effectively improve obesity in mice caused by HFD and the potential mechanisms was related to the regulation of serum levels of leptin and IL-27, lipogenesis and lipolysis in adipose tissue and gut microbiota composition.

Multi-omics reveals Dengzhan Shengmai formulation ameliorates cognitive impairments in D-galactose-induced aging mouse model by regulating CXCL12/CXCR4 and gut microbiota

Dengzhan Shengmai (DZSM), a traditional Chinese medicine formulation, has been administered extensively to elderly individuals with cognitive impairment (CI). However, the underlying mechanisms by which Dengzhan Shengmai improves cognitive impairment remains unknown. This study aimed to elucidate the underlying mechanism of the effect of Dengzhan Shengmai on aging-associated cognitive impairment via a comprehensive combination of transcriptomics and microbiota assessment. Dengzhan Shengmai was orally administered to a D-galactose-induced aging mouse model, and evaluation with an open field task (OFT), Morris water maze (MWM), and histopathological staining was performed. Transcriptomics and 16S rDNA sequencing were applied to elucidate the mechanism of Dengzhan Shengmai in alleviating cognitive deficits, and enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (PCR), and immunofluorescence were employed to verify the results. The results first confirmed the therapeutic effects of Dengzhan Shengmai against cognitive defects; specifically, Dengzhan Shengmai improved learning and impairment, suppressed neuro loss, and increased Nissl body morphology repair. Comprehensive integrated transcriptomics and microbiota analysis indicated that chemokine CXC motif receptor 4 (CXCR4) and its ligand CXC chemokine ligand 12 (CXCL12) were targets for improving cognitive impairments with Dengzhan Shengmai and also indirectly suppressed the intestinal flora composition. Furthermore, in vivo results confirmed that Dengzhan Shengmai suppressed the expression of CXC motif receptor 4, CXC chemokine ligand 12, and inflammatory cytokines. This suggested that Dengzhan Shengmai inhibited CXC chemokine ligand 12/CXC motif receptor 4 expression and modulated intestinal microbiome composition by influencing inflammatory factors. Thus, Dengzhan Shengmai improves aging-related cognitive impairment effects via decreased CXC chemokine ligand 12/CXC motif receptor 4 and inflammatory factor modulation to improve gut microbiota composition.

The efficacy and safety of mecobalamin combined with Chinese medicine injections in the treatment of diabetic peripheral neuropathy: A systematic review and Bayesian network meta-analysis of randomized controlled trials

Background: In recent years, people pay more and more attention to diabetic peripheral neuropathy (DPN). As a neurotrophic agent, mecobalamin is able to repaire nerves, which has already become a consensus among experts. However, it has been found that mecobalamin has poor effect to increase nerve conduction velocity, which is an important indicator. Clinical data have shown that Chinese medicine injection, combined with mecobalamin injection, can significantly improve nerve conduction velocity of the limbs. Nevertheless, several kinds of Chinese medicine injections have been used to treat DPN. The effect of these Chinese medicine injections for DPN are various. Therefore, it is necessary to evaluate the effectiveness of Chinese medicine injections combined with mecobalamin in the treatment of DPN.

Methods: All relevant articles published before 12 March 2022 were searched in eight electronic databases. Randomized controlled trials (RCTs) on Chinese medicine injections plus Mecobalamin for DPN were identified according to inclusion criteria, and were assessed using the revised Cochrane risk of bias tool (ROB2.0). R software and stata15 was used to create the ranking probabilities and network meta-analysis.

Results: A total of 80 RCTs involving 6,980 patients were included. The results showed that mecobalamin plus Dengzhanxixin injection (ME + DZXX) ranked first in overall response rate [RR = 1.64, 95% CI (1.26, 2.21)] and median motor nerve conduction velocity [MD = 9.46, 95% CI (5.67, 13.28)]. Then, mecobalamin plus Kudiezi Injection (ME + KDZ) had the best effect in median sensory nerve conduction velocity [MD = 10.41, 95% CI (−13.31, −7.52)], and mecobalamin plus Honghua injection (ME + HH) ranked highest in common peroneal motor nerve conduction velocity [MD = 6.8, 95% CI (4.13, 9.49)] and common peroneal sensory nerve conduction velocity [MD = −6.25, 95% CI (−8.85, −3.65)].

Conclusion: This study determined the efficacy of different Chinese medicine injections combined with mecobalamin. DZXX may be the best adjunctive Chinese medicine injection for DPN patients. However, due to potential risk of bias and limited RCTs, our results need to be treated with reservations.

Scutellarein stimulates human sperm function by increasing the levels of intracellular calcium and tyrosine phosphorylation

As a kind of flavonoid, scutellarein is widely used to protect against various human diseases. Although the protective effects of scutellarein have been well studied, its influence on human reproduction remains unknown. In this research, we evaluated the effect of scutellarein on human sperm functions in vitro. Three different concentrations of scutellarein (1, 10, 100 μM) were applied to ejaculated human sperm. Fertilisation-essential functions, as well as the intracellular calcium concentration ([Ca²⁺ ]_i ) and protein-tyrosine phosphorylation, two factors which are vital for sperm function regulation, were evaluated. The results demonstrated that all concentrations of scutellarein utilised in this study could significantly increase sperm spontaneous capacitation and acrosome reaction through the enhancement of [Ca²⁺ ]_i . Besides, the level of tyrosine phosphorylation of sperm could also be increased by scutellarein. Meanwhile, the sperm motility could be improved by 10 and 100 μM scutellarein, which also make a significant enhancement in sperm penetration ability and hyperactivation. This is one of the limited studies showing the regulation of scutellarein on human spermatozoa functions and is helpful to enrich its application.

Therapeutic Potential of Leaves from Fridericia chica (Bonpl.) L. G. Lohmann: Botanical Aspects, Phytochemical and Biological, Anti-Inflammatory, Antioxidant and Healing Action

Plants of the species Fridericia chica (Bonpl.) L. G. Lohmann (Bignoniaceae), which are widely distributed in Brazil and named crajiru in the state of Amazonas, are known in folk medicine as a traditional medicine in the form of a tea for the treatment of intestinal colic, diarrhea, and anemia, among other diseases. The chemical analysis of extracts of the leaves has identified phenolic compounds, a class of secondary metabolites that provide defense for plants and benefits to the health of humans. Several studies have shown the therapeutic efficacy of F. chica extracts, with antitumor, antiviral, wound healing, anti-inflammatory, and antioxidant activities being among the therapeutic applications already proven. The healing action of F. chica leaf extract has been demonstrated in several experimental models, and shows the ability to favor the proliferation of fibroblasts, which is essential for tissue repair. The anti-inflammatory activity of F. chica has been clearly demonstrated by several authors, who suggest that it is related to the presence of 3-deoxyanthocyanidins, which is capable of inhibiting pro-inflammatory pathways such as the kappa B (NF-kB) nuclear transcription factor pathway. Another important effect attributed to this species is the antioxidant effect, attributed to phenolic compounds interrupting chain reactions caused by free radicals and donating hydrogen atoms or electrons. In conclusion, the species Fridericia chica has great therapeutic potential, which is detailed in this paper with the objective of encouraging new research and promoting the sum of efforts for the inclusion of herbal medicines in health systems around the world.

Scutellarein Attenuates Atopic Dermatitis by Selectively Inhibiting Transient Receptor Potential Vanilloid 3

BACKGROUND AND PURPOSE

Atopic dermatitis (AD) is one of the most common chronic inflammatory cutaneous diseases with unmet clinical needs. As a common ingredient found in several medicinal herbs with efficacy on cutaneous inflammatory diseases, Scutellarein (Scu) has been shown to possess anti-inflammatory and anti-proliferative activities. We aimed to evaluate the therapeutic efficacy of Scu against AD and its underlying molecular mechanism.

EXPERIMENTAL APPROACH

Efficacy of Scu on AD was evaluated in 2,4-dinitrofluorobenzene (DNFB) and carvacrol-induced dermatitis mouse models. Cytokine mRNA and serum IgE levels were examined using qPCR and ELISA, respectively. Voltage clamp recordings were used to measure currents mediated by transient receptor potential (TRP) channels. In silico docking, site-direct mutagenesis, and covalent modification were used to explore the binding pocket of Scu on TRPV3.

KEY RESULTS

Subcutaneous administration of Scu efficaciously suppresses DNFB and carvacrol-induced pruritus, epidermal hyperplasia and skin inflammation in wild type mice but has no additional benefit in Trpv3 knockout mice in the carvacrol model. Scu is a potent and selective TRPV3 channel allosteric negative modulator with an apparent affinity of 1.18 μM. Molecular docking coupled with site-direct mutagenesis and covalent modification of incorporated cysteine residues demonstrate that Scu targets the cavity formed between the pore helix and transmembrane helix S6. Moreover, Scu attenuates endogenous TRPV3 activity in human keratinocytes and inhibits carvacrol-induced proliferative and proinflammatory responses.

CONCLUSIONS AND IMPLICATIONS

Collectively, these data demonstrate that Scu ameliorates carvacrol-induced skin inflammation by directly inhibiting TRPV3, and TRPV3 represents a viable therapeutic target for AD treatment.

The Traditional Mongolian Medicine Qiqirigan-8 Effects on Lipid Metabolism and Inflammation in Obesity: Pharmacodynamic Evaluation and Relevant Metabolites

Objective: Traditional Mongolian Medicine Qiqirigan-8 (MMQ-8) is a Chinese botanical drug with effective pharmacological properties in obesity. However, the pharmacological mechanism of MMQ-8 remains unclear. This study aimed to determine the active metabolites of MMQ-8 and its therapeutic effects on lipid metabolism and inflammation.

Methods: The active metabolites of MMQ-8 were identified by ultrahigh-performance liquid chromatograph Q extractive mass spectrometry (UHPLC-QE-MS) assay and network analysis. An obesity rat model induced by high-fat diet was used in the study. Serum levels of lipids and inflammatory factors were detected using biochemical analysis and enzyme-linked immunosorbent assay (ELISA). Pathological analysis of liver tissues and arteries was conducted with hematoxylin and eosin (H&E) staining and immunohistochemistry. Protein expression of the tumor necrosis factor (TNF) signaling pathway was investigated by Western-blot. Simultaneously, bone marrow cells were used for RNA sequencing and relevant results were validated by cell culture and quantitative real-time polymerase chain reaction (RT-qPCR).

Results: We identified 69 active metabolites and 551 target genes of MMQ-8. Of these, there are 65 active metabolites and 225 target genes closely related to obesity and inflammation. In vivo, we observed that MMQ-8 had general decreasing effects on body weight, white adipose tissue weight, and serum lipids. MMQ-8 treatment notably decreased the liver function markers and hepatic steatosis, and significantly decreased inflammation. In serum, it notably decreased TNF-α, interleukin (IL)-6, and inducible nitric oxide synthase (INOS), while elevating IL-10 levels. MMQ-8 treatment also significantly inhibited proteins phosphorylation of nuclear factor-kappa B inhibitor alpha (IκBα), mitogen-activated protein kinase (p38), extracellular regulated kinase 1/2(ERK1/2), and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and decreased vascular endothelium damage and macrophage infiltration and polarization to M1. These findings coincide with the RNA-sequencing data of bone marrow cells and results of in vitro experiments.

Conclusion: We determined the pharmacological actions and relevant metabolites of MMQ-8 in obesity for the first time. Our study revealed MMQ-8 can optimize lipid metabolism and reduce chronic inflammation in obesity. However, more in-depth research is needed, for example, to understand the principle of compound compatibility and the inhibition effects on hepatic steatosis, T cell differentiation, and inflammatory signal transduction.

Scutellarein in organic solvents: changes in spectroscopic properties caused by solute-solvent interactions

In this work, the spectroscopic properties of scutellarein (6-hydroxyapigenin) were studied in three organic solvents (methanol, acetonitrile and N,N-dimethylformamide) taking into account possible ionization and isomerization (tautomerization) processes. Significant visible colour changes were reported in the case of scutellarein in N,N-dimethylformamide. It was shown that isomerization processes can be one of the reasons for the observed changes in absorption spectrum, because some scutellarein isomers have an absorption band at about 623 nm while other forms of scutellarein show no absorption in this region. Moreover, spectroscopic properties were studied for cases of scutellarein in acetonitrile and methanol. The molar extinction coefficient has been found in the case of methanol solution which could be used to determine scutellarein concentration in this solvent using spectroscopic methods in future studies. The quantum-chemical calculations were performed for neutral and anionic forms and for two types of possible isomers of scutellarein in each solvent. The results help explain the experimentally observed rising absorption in the 500-750 nm wavelength range. Another important result of the quantum-chemical calculations is a prediction of excited state intramolecular proton transfer (ESIPT) in scutellarein. This result has been obtained for free molecule in vacuum and in the cases of methanol, acetonitrile and N,N-dimethylformamide solution. It was found that the excited state energy of the normal molecular form is higher than the excited state energy of the tautomer form of scutellarein.

Role of Bioactive Compounds in Obesity: Metabolic Mechanism Focused on Inflammation

Obesity is a disease characterized by an inflammatory process in the adipose tissue due to diverse infiltrated immune cells, an increased secretion of proinflammatory molecules, and a decreased secretion of anti-inflammatory molecules. On the other hand, obesity increases the risk of several diseases, such as cardiovascular diseases, diabetes, and cancer. Their treatment is based on nutritional and pharmacological strategies. However, natural products are currently implemented as complementary and alternative medicine (CAM). Polyphenols and fiber are naturally compounds with potential action to reduce inflammation through several pathways and play an important role in the prevention and treatment of obesity, as well as in other non-communicable diseases. Hence, this review focuses on the recent evidence of the molecular mechanisms of polyphenols and dietary fiber, from Scopus, Science Direct, and PubMed, among others, by using key words and based on recent in vitro and in vivo studies.

A Comprehensive Review on Anti-obesity Potential of Medicinal Plants and their Bioactive Compounds

Background:

Obesity is a complex health and global epidemic issue. It is an increasing global health challenge covering significant social and economic costs. Abnormal accumulation of fat in the body may increase the health risks including diabetes, hypertension, osteoarthritis, sleep apnea, cardiovascular diseases, stroke and cancer. Synthetic drugs available on the market reported to have several side effects. Therefore, the management of obesity got to involve the traditional use of medicinal plants which helps to search the new therapeutic targets and supports the research and development of anti-obesity drugs.

Objective:

This review aim to update the data and provide a comprehensive report of currently available knowledge of medicinal plants and phyto-chemical constituents reported for their anti-obesity activity.

Methodology:

An electronic search of the periodical databases like Web of Science, Scopus, PubMed, Scielo, Niscair, ScienceDirect, Springerlink, Wiley, SciFinder and Google Scholar with information reported the period 1991-2019, was used to retrieve published data.

Results:

A comprehensive report of the present review manuscript is an attempt to list the medicinal plants with anti-obesity activity. The review focused on plant extracts, isolated chemical compounds with their mechanism of action and their preclinical experimental model, clinical studies for further scientific research.

Conclusion:

This review is the compilation of the medicinal plants and their constituents reported for the managements of obesity. The data will fascinate the researcher to initiate further research that may lead to the drug for the management of obesity and their associated secondary complications. Several herbal plants and their respective lead constituents were also screened by preclinical In-vitro and In-vivo, clinical trials and are effective in the treatment of obesity. Therefore, there is a need to develop and screen large number of plant extracts and this approach can surely be a driving force for the discovery of anti-obesity drugs from medicinal plants.

Natural Products Targeting Liver X Receptors or Farnesoid X Receptor

Nuclear receptors (NRs) are a superfamily of transcription factors induced by ligands and also function as integrators of hormonal and nutritional signals. Among NRs, the liver X receptors (LXRs) and farnesoid X receptor (FXR) have been of significance as targets for the treatment of metabolic syndrome-related diseases. In recent years, natural products targeting LXRs and FXR have received remarkable interests as a valuable source of novel ligands encompassing diverse chemical structures and bioactive properties. This review aims to survey natural products, originating from terrestrial plants and microorganisms, marine organisms, and marine-derived microorganisms, which could influence LXRs and FXR. In the recent two decades (2000-2020), 261 natural products were discovered from natural resources such as LXRs/FXR modulators, 109 agonists and 38 antagonists targeting LXRs, and 72 agonists and 55 antagonists targeting FXR. The docking evaluation of desired natural products targeted LXRs/FXR is finally discussed. This comprehensive overview will provide a reference for future study of novel LXRs and FXR agonists and antagonists to target human diseases, and attract an increasing number of professional scholars majoring in pharmacy and biology with more in-depth discussion.

The potential of immature poken (Citrus reticulata) extract in the weight management, lipid and glucose metabolism

OBJECTIVES

The prevalence of obesity was increasing globally, with nearly half a billion of the world's population now considered to be overweight or obese. The immature poken (Citrus reticulata) was a good source of flavonoids and phenolic acids, which may exert an anti-obesity effect. However, the current efficacy in clinical trials was still unclear. Thus, the object of this study was to explore whether immature poken had an anti-obesity effect in the clinical trial.

METHODS

In this study, we identified nine major compounds from immature poken extract (IPE), and most compounds significantly decreased the lipid accumulation in adipocytes. In addition, 20 subjects with body mass index (BMI) ≥ 24 or body fat > 30 were recruited and randomly allocated to placebo and experimental (IPE) groups for 6 week intervention and 2 week follow-up.

RESULTS

In comparison with the baseline results (week 0), the body weight, body fat, and waist circumference at week 6 in the IPE group were significantly decreased by 1.49 kg, 0.33%, 2.1 cm. Moreover, in blood biochemical analysis, total cholesterol (TC), triglyceride (TG), fasting blood sugar (FBS), and insulin levels at week 6 in IPE group were also decreased by 3.6, 4.6, 2.1 (mg/dL), and 2.9 (μU/mL), respectively.

CONCLUSIONS

The finding showed that immature poken had important roles in fat metabolism by suppressing adipogenesis, and immature poken may provide new weight loss strategies for obese people.

Kaempferide improves glycolipid metabolism disorder by activating PPARγ in high-fat-diet-fed mice

AIMS

Kaempferide (Ka, 3,5,7-trihydroxy-4'-methoxyflavone), an active ingredient of Tagetes erecta L., has been demonstrated to possess many pharmacological effects, including antioxidant, anti-inflammation, anticancer and antihypertension in previous study. However, there is no evidence of Ka on metabolic disorder in former studies. This study investigated the effects of Ka on glycolipid metabolism and explored the underlying mechanisms of action in vivo and vitro.

MATERIALS AND METHODS

The mouse model of glycolipid metabolism disorder was induced by high-fat diet (HFD). The effects of Ka were evaluated on bodyweight, lipid metabolism and glucose metabolism. Hypolipidemic effect was examined by blood sample analysis. The hypoglycemic effect was detected by several indicators, like blood glucose, serum insulin, HOMA index and intraperitoneal glucose tolerance tests (IPGTT). The signaling pathways of lipid metabolism (PPARγ/LXRα/ABCA1) and glucose metabolism (PPARγ/PI3K/AKT) were evaluated using Real-Time PCR and Western blot. The primary culture of hepatocyte was prepared to confirm the target of Ka by co-culturing with PPARγ agonist or inhibitor.

KEY FINDINGS

The HFD mice developed obesity, hyperlipidemia, hyperglycemia and insulin resistance. Administration of Ka at a dose of 10 mg/kg.BW for 16 weeks effectively attenuated these changes. Further studies revealed the hypolipidemic and hypoglycemic effects of Ka depended on the activation of PPARγ/LXRα/ABCA1 and PPARγ/PI3K/AKT pathways, respectively. The primary hepatocyte test, co-cultured with PPARγ agonists or inhibitors, further confirmed the above signaling pathway and key protein.

SIGNIFICANCE

These results suggested that Ka played an important role in improving glycolipid metabolism disorder. These favorable effects were causally associated with anti-obesity. The underlying mechanisms might have to do with the activation of the PPARγ and its downstream signaling pathway. Our study helped to understand the pharmacological actions of Ka, and played a role for Ka in the effective treatment of obesity, diabetes, nonalcoholic hepatitis and other metabolic diseases.

A comprehensive study of the metabolism of flavonoid oroxin B in vivo and in vitro by UHPLC-Q-TOF-MS/MS

Oroxin B, a flavonoid, is a major bioactive component form Oroxylum indicum (L.) Vent. with enormous anti-hepatoma effects. To data, the oroxin B metabolism studies remain underexplored. This study was designed to characterize oroxin B metabolism in vivo and in vitro by ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS). Consequently, 30 metabolites in rats, 8 metabolites in liver microsomes and 18 metabolites in intestinal bacteria were identified, and 9 metabolites were recognized by comparison with standards. The biotransformation processes involved ketone, acetylation, loss of C₁₂H₂₀O₁₀, and loss of C₆H₁₀O₅. And baicalein and oroxin A were generated after loss of C₁₂H₂₀O₁₀, and loss of C₆H₁₀O₅, respectively, and further went through some other reactions, such as oxidation, methylation, internal hydrolysis, hydrogenation, loss of O, ketone, glycine conjugation, glucuronide conjugation and their composite reactions. The results provide valuable evidence for elucidation the potential mechanism of oroxin B pharmacological action, and offer reasonable guidelines for further investigations of oroxin B safety and efficacy.

Artemisinin and dihydroartemisinin promote β-cell apoptosis induced by palmitate via enhancing ER stress

Artemisinin (ART) and dihydroartemisinin (DHA) are first-line antimalarial drugs and have been reported to have anti-obesity effects. Hyperlipidemia is associated with β-cell damage in obese subjects, which could contribute to the pathogenesis of type 2 diabetes. In addition to their anti-obesity effects, ART and DHA also have protective roles in some diseases. Thus, we investigated the effects of ART and DHA in palmitate-induced β-cell apoptosis and the underlying mechanism. In this study, the rat pancreatic β-cell line INS-1 and mouse pancreatic β-cell line MIN6 were cultured with palmitate (PA) (0.1 mM) to induce cell apoptosis in the presence or absence of ART or DHA. Cell apoptosis was investigated by using flow cytometry, and the expression of ER stress markers, including CHOP, GRP78 and PDI, was detected by Western blotting and/or qRT-PCR. The results showed that ART and DHA significantly increased the apoptosis of β-cells induced by PA and exacerbated the ER stress caused by PA. An inhibitor of ER stress, 4-phenylbutyric acid (4-PBA), significantly ameliorated cell apoptosis caused by ART and DHA in PA-treated β-cells, consistent with the inhibition of ER stress. Together, the findings from the current study suggested that ART and DHA may promote lipid disorder-associated β-cell injury via enhancing ER stress when they were used to treat obesity.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

Scutellarein inhibits BLM-mediated pulmonary fibrosis by affecting fibroblast differentiation, proliferation, and apoptosis

Introduction

Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible interstitial pulmonary disease that has a poor prognosis. Scutellarein, which is extracted from the traditional Chinese medicine Erigeron breviscapus, is used to treat a variety of diseases; however, the use of scutellarein for the treatment of pulmonary fibrosis and the related mechanisms of action have not been fully explored.

Methods

This study was conducted using a well-established mouse model of pulmonary fibrosis induced by bleomycin (BLM). The antifibrotic effects of scutellarein on histopathologic manifestations and fibrotic marker expression levels were examined. The effects of scutellarein on fibroblast differentiation, proliferation, and apoptosis and on related signaling pathways were next investigated to demonstrate the underlying mechanisms.

Results

In the present study, we found that scutellarein alleviated BLM-induced pulmonary fibrosis, as indicated by histopathologic manifestations and the expression levels of fibrotic markers. Further data demonstrated that the ability of fibroblasts to differentiate into myofibroblasts was attenuated in scutellarein-treated mice model. In addition, we obtained in vitro evidence that scutellarein inhibited fibroblast-to-myofibroblast differentiation by repressing TGF-β/Smad signaling, inhibited cellular proliferation by repressing PI3K/Akt signaling, and increased apoptosis of fibroblasts by affecting Bax/Bcl2 signaling.

Discussion

In general, scutellarein might exert therapeutic effects on pulmonary fibrosis by altering the differentiation, proliferation, and apoptosis of fibroblasts. Although scutellarein has been demonstrated to be safe in mice, further studies are required to investigate the efficacy of scutellarein in patients with IPF.

The anti-insulin resistance effect of scutellarin may be related to antioxidant stress and AMPKα activation in diabetic mice

AIMS

Scutellarein (Sc), a natural compound and an active ingredient of Erigeronbrevis-capus (Vant.), shows anti-obesity, anti-inflammation and lipid-lowering properties in our previous study. However, no previous in vivo and vitro has been conducted to assess the effects of Sc in insulin resistance (IR). This study investigated the effects of Sc on IR and oxidative stress and explored the underlying mechanisms of action in vivo and vitro.

MATERIAL AND METHOD

A well-established mouse model of IR, induced by high-fat diet (HFD) feeding, was applied in this study. The effects of Sc were evaluated on obesity, glycometabolism disorder and oxidative stress. The anti-IR effect was assessed using blood glucose, serum insulin, HOMA index, intraperitoneal glucose tolerance tests (IPGTT), intraperitoneal insulin tolerance tests (IPITT), and glucose-regulating enzyme activity. The insulin signaling pathways and AMPKα expressions were tested by Western blot. The primary culture of hepatocytes was prepared and used for confirming the above signaling pathways.

RESULTS

Obesity, IR and oxidative stress developed in HFD mice. Administration of Sc at a dose of 50mg/kg for 16 weeks effectively attenuated these changes. Further studies revealed the antagonistic effect of Sc on IR was a result of the activation of the insulin signaling pathway and AMPKα. The primary hepatocyte test, stimulated by high glucose, further confirmed that SC exerts anti-IR through the above signaling pathway and key protein.

CONCLUSION

These results suggested that Sc possesses not only an important novel anti-IR effect but also an anti-oxidative stress effect. These favorable effects were causally associated with weight loss and the improved glycometabolism. The underlying mechanisms might associated with the activation of the insulin signaling pathway and AMPKα. Our study promotes the understanding of the pharmacological actions of Sc, and plays a role for Sc in the effective treatment of diabetes mellitus.

Aromatic Herbs, Medicinal Plant-Derived Essential Oils, and Phytochemical Extracts as Potential Therapies for Coronaviruses: Future Perspectives

After its recent discovery in patients with serious pneumonia in Wuhan (China), the 2019 novel coronavirus (2019-nCoV), named also Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has spread quickly. Unfortunately, no drug or vaccine for treating human this coronavirus infection is available yet. Numerous options for controlling or preventing emerging 2019-nCoV infections may be predicted, including vaccines, interferon therapies, and small-molecule drugs. However, new interventions are likely to require months to years to develop. In addition, most of the existing antiviral treatments frequently lead to the development of viral resistance combined with the problem of side effects, viral re-emergence, and viral dormancy. The pharmaceutical industry is progressively targeting phytochemical extracts, medicinal plants, and aromatic herbs with the aim of identifying lead compounds, focusing principally on appropriate alternative antiviral drugs. Spices, herbal medicines, essential oils (EOs), and distilled natural products provide a rich source of compounds for the discovery and production of novel antiviral drugs. The determination of the antiviral mechanisms of these natural products has revealed how they interfere with the viral life cycle, i.e., during viral entry, replication, assembly, or discharge, as well as virus-specific host targets. Presently, there are no appropriate or approved drugs against CoVs, but some potential natural treatments and cures have been proposed. Given the perseverance of the 2019-nCoV outbreak, this review paper will illustrate several of the potent antiviral chemical constituents extracted from medicinal and aromatic plants, natural products, and herbal medicines with recognized in vitro and in vivo effects, along with their structure-effect relationships. As this review shows, numerous potentially valuable aromatic herbs and phytochemicals are awaiting assessment and exploitation for therapeutic use against genetically and functionally different virus families, including coronaviruses.