Isoliquiritigenin, a flavonoid from licorice, plays a dual role in regulating gastrointestinal motility in vitro and in vivo

Methods for Overcoming Chemoresistance in Head and Neck Squamous Cell Carcinoma: Keeping the Focus on Cancer Stem Cells, a Systematic Review

According to the "cancer stem cell" (CSCs) theory, tumors are a diverse and expanding group of malignant cells that originate from a small number of CSCs. Despite treatment, these cells can still become active and proliferate, which can result in distant metastasis and local recurrences. A new paradigm in cancer treatment involves targeting both CSCs and the cancer cells in a tumor. This review aims to examine the literature on methods published to overcome chemoresistance due to the presence of CSCs in head and neck cancers. The review was registered with PROSPERO (ID# CRD42024512809). After Pub Med, Scopus, and WoS database searches, 31 relevant articles on oral squamous cell carcinoma (OSCC) were selected. Compounds that increased chemosensitivity by targeting CSCs in head and neck squamous cell carcinoma (HNSCC) were divided into (1) natural products, (2) adjuvant molecules to traditional chemotherapy, and (3) CSCs targeting patient-specific fresh biopsies for functional precision medicine.

Utilizing non-coding RNA-mediated regulation of ATP binding cassette (ABC) transporters to overcome multidrug resistance to cancer chemotherapy

Multidrug resistance (MDR) is one of the primary factors that produces treatment failure in patients receiving cancer chemotherapy. MDR is a complex multifactorial phenomenon, characterized by a decrease or abrogation of the efficacy of a wide spectrum of anticancer drugs that are structurally and mechanistically distinct. The overexpression of the ATP-binding cassette (ABC) transporters, notably ABCG2 and ABCB1, are one of the primary mediators of MDR in cancer cells, which promotes the efflux of certain chemotherapeutic drugs from cancer cells, thereby decreasing or abolishing their therapeutic efficacy. A number of studies have suggested that non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), play a pivotal role in mediating the upregulation of ABC transporters in certain MDR cancer cells. This review will provide updated information about the induction of ABC transporters due to the aberrant regulation of ncRNAs in cancer cells. We will also discuss the measurement and biological profile of circulating ncRNAs in various body fluids as potential biomarkers for predicting the response of cancer patients to chemotherapy. Sequence variations, such as alternative polyadenylation of mRNA and single nucleotide polymorphism (SNPs) at miRNA target sites, which may indicate the interaction of miRNA-mediated gene regulation with genetic variations to modulate the MDR phenotype, will be reviewed. Finally, we will highlight novel strategies that could be used to modulate ncRNAs and circumvent ABC transporter-mediated MDR.

Isoliquiritigenin inhibits gastric cancer growth through suppressing GLUT4 mediated glucose uptake and inducing PDHK1/PGC-1α mediated energy metabolic collapse

BACKGROUND

Isoliquiritigenin (ISL), a natural flavonoid, has anti-tumor activity. But, the understanding of the impact and molecular mechanism of ISL on the growth of gastric cancer (GC) remains limited.

PURPOSE

The study was to explore the tumor suppressive effect of ISL on GC growth both in vitro and in vivo, meanwhile, clarify its molecular mechanisms.

METHODS

Cell viability was detected by cell counting kit-8 (CCK-8) assay. Apoptotic cells in vitro were monitored by Hoechst 33,342 solution. Protein expression was assessed by Western blot. Reactive oxygen species (ROS) level was evaluated by utilizing 2',7'- dichlorofluorescin diacetate (DCFH-DA). Lactic acid level was detected with L-lactate assay kit. Glucose uptake was monitored with fluorescently tagged glucose 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Glycolytic proton efflux rate (GlycoPER) was evaluated by glycolytic rate assay kit. Oxygen consumption rate (OCR) was conducted by mito stress test kit. A nude mouse model of gastric cancer cell xenograft was established by subcutaneous injection with MGC803 cells. Pathological changes were evaluated by using H&E staining. Cell apoptosis in vivo was evaluated by terminal deoxy-nucleotide transferase mediated dUTP nick end labeling (TUNEL) assay.

RESULTS

ISL remarkably suppressed GC growth and increased cell apoptosis. It regulated apoptosis-related and metabolism-related protein expression both in vitro and in vivo. ISL blocked glucose uptake and suppressed production and secretion of lactic acid, which was accompanied with suppressed mitochondrial oxidative phosphorylation (OXPHOS) and glycolysis but increased ROS accumulation. Overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α), cellular-myelocytomatosis viral oncogene (c-Myc), hypoxia inducible factor-1α (HIF-1α), glucose transporter 4 (GLUT4) or pyruvate dehydrogenase kinase 1 (PDHK1), could abolish ISL-induced inhibition of cell viability in GC cells.

CONCLUSION

These findings implicated that ISL inhibits GC growth by decreasing GLUT4 mediated glucose uptake and inducing PDHK1/PGC-1α-mediated energy metabolic collapse through depressing protein expression of c-Myc and HIF-1α in GC, suggesting its potential application for GC treatment.

Exploring the mechanism of solubilization and release of isoliquiritigenin in deep eutectic solvents

Isoliquiritigenin (ISL) is a natural medicinal product with extensive pharmacological activities. However, its low solubility limits its application. Therefore, this study aimed to explore the solubilization and release mechanism of the ISL using deep eutectic solvents (DESs). The choline chloride (ChCl) and oxalic acid (OA)/malic acid (MA)/gallic acid (GA) were used to synthesize ChCl-OA/MA/GA DESs, and the solubility of ISL in these DESs was studied to explore the solubilization mechanism of ISL. The thermodynamic properties of DESs were characterized using differential scanning calorimetry (DSC). The molecular interactions in DESs were studied using spectroscopy and molecular dynamics (MD) simulations. The relative density of DESs was measured using a pycnometric method, its accuracy was validated by comparing it with the MD simulation. The release of ISL from ChCl-OA/MA/GA eutectogels was studied using Carbomer 940 as the thickener, and the release mechanism of ISL in the eutectogels was explored by the drug release kinetic model. The solubility study found that the solubility of ISL in ChCl-OA/MA/GA DESs is 30073, 5055, and 68,103 times higher than that in an aqueous solution. In addition, further studies using MD simulations revealed that enhancing the interactions between ISL and solvent molecules can improve the solubility of ISL in DESs. In vitro release studies showed that the release of ISL in ChCl-OA/MA/GA eutectogels followed a first-order release model, with correlation coefficients of 0.9812, 0.9916, and 0.9961, respectively. In conclusion, the study of the solubilization and release mechanism of ISL in DESs provides new ideas and methods for the study of poorly soluble drugs, which is expected to improve the efficacy and clinical application value of drugs.

The traditional herbal medicines mixture, Banhasasim-tang, relieves the symptoms of irritable bowel syndrome via modulation of TRPA1, NaV1.5 and NaV1.7 channels

ETHNOPHARMACOLOGICAL RELEVANCE

The cause of irritable bowel syndrome (IBS), a functional gastrointestinal (GI) disorder, remains unclear. Banhasasim-tang (BHSST), a traditional herbal medicines mixture, mainly used to treat GI-related diseases, may have a potential in IBS treatment. IBS is characterized by abdominal pain as the main clinical symptom, which seriously affects the quality of life.

AIM OF THE STUDY

We conducted a study to evaluate the effectiveness of BHSST and its mechanisms of action in treating IBS.

MATERIALS AND METHODS

We evaluated the efficacy of BHSST in a zymosan-induced diarrhea-predominant animal model of IBS. Electrophysiological methods were used to confirm modulation of transient receptor potential (TRP) and voltage-gated Na⁺ (NaV) ion channels, which are associated mechanisms of action.

RESULTS

Oral administration of BHSST decreased colon length, increased stool scores, and increased colon weight. Weight loss was also minimized without affecting food intake. In mice administered with BHSST, the mucosal thickness was suppressed, making it similar to that of normal mice, and the degree of tumor necrosis factor-α was severely reduced. These effects were similar to those of the anti-inflammatory drug-sulfasalazine-and antidepressant-amitriptyline. Moreover, pain-related behaviors were substantially reduced. Additionally, BHSST inhibited TRPA1, NaV1.5, and NaV1.7 ion channels associated with IBS-mediated visceral hypersensitivity.

CONCLUSIONS

In summary, the findings suggest that BHSST has potential beneficial effects on IBS and diarrhea through the modulation of ion channels.

Detection and isolation of intestinal muscle relaxant substances from the root of Taverniera abyssinica A. Rich

ETHNOPHARMACOLOGICAL RELEVANCE

In Ethiopian traditional medicine the root of Taverniera abyssinica A.Rich is known as a remedy for sudden gastrointestinal cramping and fever. In this study we have isolated and identified the bioactive principle of Taverniera abyssinica that exerts effects on isolated smooth muscle tissues of the rabbit duodenum and guinea-pig ileum.

AIM OF THE STUDY

To isolate and purify the bioactive principle from the root of Taverniera abyssinica A.Rich by bioassay-guided fractionation, HPLC purification and masspectrometry, with further investigation of its bioactivity on isolated smooth muscle strips.

MATERIALS AND METHODS

Roots of Taverniera abyssinica A.Rich extracted in 75% methanol/water were fractioned with a reverse phase column and then subjected to HPLC purification. Each fraction collected from the HPLC was tested for its bioactivity using electric field stimulation-evoked contractions of the rabbit duodenum and guinea-pig ileum. Finally, detailed structural analysis of the fraction displaying significant bioactivity was made by mass spectrometry.

RESULTS

Through bioassay-guided fractionation and HPLC purification the bioactive fractions were identified. These were tested for bioactivity on isolated smooth muscle strips which showed about 80% inhibition of contractions evoked by electric field stimulation. These compounds were identified as formononetin, afrormosin and tectorigenin by using masspectrometry applying relevant standards for detection.

CONCLUSION

The traditionally claimed smooth muscle-relaxing effect of the roots of Taverniera abyssinica A.Rich is essentially due the three isolated and purified the two isoflavones formononetin, afrormosin as well as the metoxyisoflavone tectorigenin, along with possibly other not yet purified bioactive substances, however with similar smooth muscle-relaxing properties.

Bidirectional Effects of Mao Jian Green Tea and Its Flavonoid Glycosides on Gastrointestinal Motility

Mao Jian Tea (MJT) has been generally consumed as a digestive aid for more than a hundred years in the Shanxi province of China. However, determination of its efficacy still remains elusive. This study investigated the effect of Mao Jian Green Tea (MJGT) on gastrointestinal motility. The biphasic effects of the hydro extracts of MJGT on gastric emptying and small intestinal propulsion of rats were identified in vivo; namely, the low (MJGT_L) and medium (MJGT_M) concentrations promoted gastrointestinal motility (p < 0.05), whereas the high concentration (MJGT_H) showed the opposite effect (p < 0.01). The expression levels of the gastric hormones, GAS, MTL and VIP (p < 0.05) were consistent with the gastrointestinal motility variation, with the exception of MTL in MJGT_H group (p > 0.01). Two flavonoids, eriodictyol (0.152 mg/mL) and luteolin (0.034 mg/mL), and the corresponding glycosides eriodictyol-7-O-glucoside (0.637 mg/mL) and luteolin-7-O-glucoside (0.216 mg/mL), dominated the hydro extracts identified by HPLC and UPLC-ESI-MS. These compounds can regulate the muscle strip contractions isolated from the gastrointestinal tissues. Additionally, the different concentrations also influenced the gut microbiota accordingly characterized by 16S rDNA gene sequencing. The MJGT_L boosted several probiotic bacteria, such as Muribaculaceae (1.77-fold), Prevotellaceae (1.85-fold) and Lactobacillaceae (2.47-fold), and suppressed the pathogenic species such as Staphylococcaceae (0.03-fold) that, conversely, was enriched in the MJGT_H group (1.92-fold). Therefore, the biphasic effect indicated that the dosage of the herbal tea should not be overlooked.

Investigation of the potential of Glycyrrhiza glabra as a bioavailability enhancer of Vitamin B12

Vitamin B12 deficiency is prevalent among individuals globally. Inadequate consumption of B12 rich diet and low bioavailability (due to diet based/physiological factors) are linked to the deficiency of Vitamin B12 inside the body. Bioavailability enhancers augment the bioavailability of an ingested substance (drug/nutrient) thus increasing their concentration inside the body and maximizing their therapeutic benefits. In traditional medicine, Licorice (Glycyrrhiza glabra) finds utility in the treatment of various health conditions. Thus, the present study aimed to examine the potential of ethanolic extract obtained from G. glabra roots to enhance the bioavailability of Vitamin B12. The effect of ethanolic extract of G. glabra (GgEtOH) on intestinal absorption enhancement of B12 was assessed in vitro on Caco-2 and ex-vivo everted gut sac models. The influence of extract on the pharmacokinetics of Vitamin B12 was determined in vivo in Swiss albino mice. GgEtOH significantly enhanced the permeation (Papp) of B12 by 2-5 fold in vitro (25, 50, and 100 μg/ml concentrations) and ex-vivo (250 and 500 μg/ml concentrations). The pharmacokinetic parameters of B12 such as Cmax, AUC, Tmax, etc. were also significantly elevated in vivo upon oral administration of B12 (1 mg/kg dose) in combination with GgEtOH (100 and 1,000 mg/kg dose). These preliminary findings indicate that the ethanolic extract of G. glabra is capable of enhancing the bioavailability of Vitamin B12. To the best of our knowledge, this is the first report to demonstrate herbal extract-mediated enhancement of Vitamin B12 bioavailability through in vitro, ex vivo, and in vivo assays.

Treatment of Gastrointestinal Disorders-Plants and Potential Mechanisms of Action of Their Constituents

The worldwide prevalence of gastrointestinal diseases is about 40%, with standard pharmacotherapy being long-lasting and economically challenging. Of the dozens of diseases listed by the Rome IV Foundation criteria, for five of them (heartburn, dyspepsia, nausea and vomiting disorder, constipation, and diarrhoea), treatment with herbals is an official alternative, legislatively supported by the European Medicines Agency (EMA). However, for most plants, the Directive does not require a description of the mechanisms of action, which should be related to the therapeutic effect of the European plant in question. This review article, therefore, summarizes the basic pharmacological knowledge of synthetic drugs used in selected functional gastrointestinal disorders (FGIDs) and correlates them with the constituents of medicinal plants. Therefore, the information presented here is intended as a starting point to support the claim that both empirical folk medicine and current and decades-old treatments with official herbal remedies have a rational basis in modern pharmacology.

Antioxidant and Anti-Melanogenic Activities of Heat-Treated Licorice (Wongam, Glycyrrhiza glabra × G. uralensis) Extract

Melanin is a brown or black pigment that protects skin from ultraviolet radiation and reactive oxygen species (ROS). However, overproduction of melanin is associated with lentigines, melasma, freckles and skin cancer. Licorice has shown antioxidant, anti-tumor, anti-platelet, anti-inflammatory and immunomodulatory activities and is used as a natural treatment for skin whitening. We aimed to confirm the potential of Wongam, a new cultivar of licorice developed by the Rural Development Administration (RDA), as a whitening agent in cosmetics. In addition, we verified the effect of heat treatment on the bioactivity of licorice by comparing antioxidant and anti-melanogenic activities of licorice extract before and after heating (130 °C). The heat-treated licorice extract (WH-130) showed higher radical-scavenging activities in the ABTS⁺ (2,2′-azino-bis-(3-ethylbenzothiazolin-6-sulfonic acid) diammonium salt) and DPPH (2,2-diphenyl-1-picrylhydrazyl) assays. In addition, WH-130 inhibited melanogenesis more effectively due to downregulation of tyrosinase in B16F10 melanoma cells than non-heated licorice extract. Moreover, heat treatment increased total phenolic content. In particular, isoliquiritigenin, an antioxidant and anti-melanogenic compound of licorice, was produced by heat treatment. In conclusion, WH-130, with increased levels of bioactive phenolics such as isoliquiritigenin, has potential for development into a novel skin whitening material with applications in cosmetics.

Administration of isoliquiritigenin prevents nonalcoholic fatty liver disease through a novel IQGAP2-CREB-SIRT1 axis

Isoliquiritigenin (ISO) is a flavonoid extracted from the root of licorice, which serves various biological and pharmacological functions including antiinflammatory, antioxidation, liver protection, and heart protection. However, the mechanism of its action remains elusive and the direct target proteins of ISO have not been identified so far. Through cell-based screening, we identified ISO as a potent lipid-lowering compound. ISO treatment successfully ameliorated fatty acid-induced cellular lipid accumulation and improved nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) by increasing PPARα-dependent lipid oxidation and decreasing SREBPs-dependent lipid synthesis. Both these signaling required the activation of SIRT1. Knockdown of SIRT1 resulted in the reversal of ISO beneficiary effects suggesting that the lipid-lowering activity of ISO was regulated by SIRT1 expression. To identify the direct target of ISO, limited proteolysis combined with mass spectrometry (LiP-SMap) strategy was applied and IQGAP2 was identified as the direct target for ISO in regulating lipid homeostasis. In the presence of ISO, both mRNA and protein levels of SIRT1 were increased; however, this effect was abolished by blocking IQGAP2 expression using siRNA. To explore how IQGAP2 regulated the expression level of SIRT1, proteome profiler human phospho-kinase array kit was used to reveal possible phosphorylated kinases and signaling nodes that ISO affected. We found that through phosphorylation of CREB, ISO transduced signals from IQGAP2 to upregulate SIRT1 expression. Thus, we not only demonstrated the molecular basis of ISO in regulating lipid metabolism but also exhibited for the first time a novel IQGAP2-CREB-SIRT1 axis in treating NAFLD/NASH.

Isoliquiritigenin attenuates inflammation and modulates Nrf2/caspase-3 signalling in STZ-induced aortic injury

OBJECTIVES

The current study provides evidence on the ameliorative impact of Isoliquiritigenin (ISL), a natural bioflavonoid isolated from licorice roots against diabetes mellitus (DM)-induced aortic injury in rats.

METHODS

DM was induced in male Sprague-Dawley rats by single I.P. injection of STZ (50 mg/kg). ISL was administrated daily (20 mg/kg, orally) for 8 wks.

KEY FINDINGS

Diabetic group showed a significant aortic injury with evidence of atherosclerotic lesions development. Daily ISL (20 mg/kg, orally) administration for 8 wks significantly restored aortic oxidative/antioxidative stress homeostasis via modulating NrF-2/Keap-1/HO-1. Moreover, ISL treatment restored aortic levels of IL-10 and dampened aortic levels of IL-6 and TNF-α. Caspase-3 expression significantly declined as well. Further, ISL treatment successfully suppressed aortic endothelin-1 (ET-1) expression and restored NO contents, eNOS immunostaining paralleled with retraction in atherosclerotic lesions development, and lipid deposition with histopathological architectural preservation and restoration of almost normal aortic thickness.

CONCLUSION

ISL can be proposed to be an effective protective therapy to prevent progression of DM-induced vascular injury and to preserve aortic integrity.

Protective effect of isoliquiritigenin on experimental diabetic nephropathy in rats: Impact on Sirt-1/NFκB balance and NLRP3 expression

The prevalence of diabetes mellitus (DM) drastically increases worldwide. Persistent hyperglycemia affects body microvasculature causing injuries to kidney producing diabetic nephropathy (DNE). Manifestation of these microvascular complications is associated with disturbed redox homeostasis. The current study evaluated the effect of isoliquiritigenin (ISLQ), a bioactive chalcone found in licorice which is known for its antioxidant effect, on diabetes-induced renal injury. DM was prompted in male rats by streptozotocin (STZ, 50 mg/kg, intraperitoneally). ISLQ was administrated by oral gavage for 8 weeks at a dose (20 mg/kg/day). Features of renal injury were observed in kidneys of diabetic rats including, albuminuria and deteriorated renal function. Renal dysfunction was associated with reduced sirtuin-1 (Sirt-1) expression, increased renal oxidative stress, nucleotide-binding domain and leucine-rich repeat containing protein-3 (NLRP3), nuclear factor-κB (NFκB) and inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). Moreover, there was significant downregulation of anti-inflammatory cytokine interleukin-10 (IL-10), glomerular and tubular injury and collagen accumulation. ISLQ administration preserved renal function and architecture, restored Sirt1 and renal oxidant-antioxidant balance, dampened inflammation and attenuated collagen accumulation. It can be inferred that ISLQ possess a protective effect and could have a potential as a food supplement to halt development and progression of DNE.

A Review: The Anti-inflammatory, Anticancer and Antibacterial Properties of Four Kinds of Licorice Flavonoids Isolated from Licorice

Plants have always been an important source of medicines for humans, and licorice is a very significant herb in the development of humans. As a traditional herb, it is widely cultivated in China, Japan, Russia, Spain and India. With the development of organic chemistry and biochemistry, various chemical ingredients extracted from licorice have been studied and identified. Among them, many chemical components were considered to have strong pharmacological activities, such as anti-inflammatory, anti-ulcer, antibacterial, anticancer and so on. Based on those reports, licorice has attracted the attention of many researchers in recent years, and they are devoted to discovering the active ingredients and mechanism of action of active compounds. Licorice flavonoids are one of the main extracts of licorice root and stem and have many potential biological properties. This paper aims to summarize the four kinds of licorice flavonoids, including liquiritigenin, isoliquiritigenin, licochalcone (including licochalcone A and licochalcone B) and glabridin, about their biological activities of anti-inflammatory, anticancer, antibacterial.

Abdel-Daim M, Prasad Devkota H. Traditional Uses, Bioactive Chemical Constituents, and Pharmacological and Toxicological Activities of Glycyrrhiza glabra L. (Fabaceae)

Traditional herbal remedies have been attracting attention as prospective alternative resources of therapy for diverse diseases across many nations. In recent decades, medicinal plants have been gaining wider acceptance due to the perception that these plants, as natural products, have fewer side effects and improved efficacy compared to their synthetic counterparts. Glycyrrhiza glabra L. (Licorice) is a small perennial herb that has been traditionally used to treat many diseases, such as respiratory disorders, hyperdipsia, epilepsy, fever, sexual debility, paralysis, stomach ulcers, rheumatism, skin diseases, hemorrhagic diseases, and jaundice. Moreover, chemical analysis of the G. glabra extracts revealed the presence of several organic acids, liquirtin, rhamnoliquirilin, liquiritigenin, prenyllicoflavone A, glucoliquiritin apioside, 1-metho-xyphaseolin, shinpterocarpin, shinflavanone, licopyranocoumarin, glisoflavone, licoarylcoumarin, glycyrrhizin, isoangustone A, semilicoisoflavone B, licoriphenone, and 1-methoxyficifolinol, kanzonol R and several volatile components. Pharmacological activities of G. glabra have been evaluated against various microorganisms and parasites, including pathogenic bacteria, viruses, and Plasmodium falciparum, and completely eradicated P. yoelii parasites. Additionally, it shows antioxidant, antifungal, anticarcinogenic, anti-inflammatory, and cytotoxic activities. The current review examined the phytochemical composition, pharmacological activities, pharmacokinetics, and toxic activities of G. glabra extracts as well as its phytoconstituents.

Glycyrrhiza glabra L. (Fabaceae/Leguminosae)

Liquorice is a perennial, temperate-zone herb or subshrub, native of India, Pakistan and southern Europe; also cultivated in England, Belgium, France, Germany, Spain, Italy, Greece, Turkey, Russia, South Africa, Egypt, Syria and Iraq. It has also been grown experimentally in the United States. Ancient historical manuscripts from China, India and Greece mention its use for symptoms of viral respiratory tract infections and hepatitis. The plant has also been described by Theophrastus. Licorice from Egypt has been described to be the best, followed by from Iraq and Syria; the root should be decorticated before use. It concocts viscid humours in diseases of liver, bladder and lungs, and expectorates them. It has been used in Iranian herbal medicine for skin eruptions, including dermatitis, eczema, pruritus and cysts, and for treatment of stomach disorders including peptic ulcers. The herb extract inhibits gastric motility in vivo, which is regarded to be an important aspect for its antiulcer activity. Licorice possesses both anti-inflammatory and antiulcer activities; whereas most anti-inflammatory agents are ulcerogenic. Former German Commission E believed it to be effective in the treatment of atopic dermatitis. Licorice root has been used for years to regulate gastrointestinal function in TCM, has been used for generations as an antidote, demulcent, and elixir in folk medicine of China, and is the most commonly used crude drug in Kampo Medicines, the Japanese form of modified TCM, for the treatment of peptic ulcer. Roots contain glycyrrhizin, the main water-soluble constituent that is 50× sweeter than sugar, 2-β-glucuronosyl glucuronic acid, and isoliquiritigenin-4-glucoside. Glycyrrhizin is a nonhemolytic saponin with foaming property, and one of the most potent hydroxyl radical scavengers. No significant effect of deglycyrrhizinised liquorice was observed on gastric ulcer in an RCT of British patients. Treatment of healthy men with licorice for one-week decreased salivary testosterone values by 26% but no significant decrease in free testosterone, and nine healthy women treated with licorice daily for two cycles, had their mean total serum testosterone decreased by 37% at the end of 2nd month. This property could be useful as an adjunct therapy of hirsutism and PCOS.

Fermented milk containing Lactobacillus paracasei and Glycyrrhiza glabra has a beneficial effect in patients with Helicobacter pylori infection: A randomized, double-blind, placebo-controlled study

BACKGROUND

Lactobacillus paracasei and Glycyrrhiza glabra have been reported as having beneficial effects on Helicobacter pylori infection. We aimed to assess the efficacy and safety of fermented milk containing L paracasei HP7 and G glabra in patients with H pylori infection.

METHODS

This multicenter, prospective, randomized, double-blind, placebo-controlled clinical trial was conducted in 2 hospitals from April to December 2017. Patients with H pylori infection were randomized into either the treatment group (fermented milk with L paracasei HP7 and G glabra) or placebo group (fermented milk only) once daily for 8 weeks. The primary endpoint was the gastric load of H pylori measured by C-urea breath test (UBT). Secondary endpoints were histologic and clinical improvement.

RESULTS

A total of 142 patients were randomly allocated to the treatment (n = 71) or placebo groups (n = 71). Compared to baseline data, the quantitative value of C-UBT at 8 weeks was significantly reduced in the treatment group (from 20.8 ± 13.2% to 16.9 ± 10.8%, P = .035), but not in the placebo group (P = .130). Chronic inflammation improved significantly only in the treatment group (P = .013), whereas the neutrophil activity deteriorated significantly only in the placebo group (P = .003). Moreover, the treatment group had significant improvement in gastrointestinal symptoms (P = .049) and quality of life (P = .029). No serious adverse events were observed.

CONCLUSION

The combination of fermented milk containing L paracasei and G glabra reduced H pylori density and improved histologic inflammation. However, their mechanisms of action should be elucidated in further studies.

Efficacy of Jianpi Liqi therapy for functional dyspepsia: A meta-analysis of randomized, positive medicine-controlled trials

BACKGROUND

We performed this meta-analysis to assess the efficacy and safety of Jianpi Liqi therapy (JLT), a traditional Chinese medicine therapy, in treating functional dyspepsia (FD).

METHODS

We systematically searched 13 databases from their inception to 15th, May 2019. Eligible studies were randomized controlled trials (RCTs) that compared JLT medicine with conventional pharmacotherapy (CP) in treating patients with FD. Cochrane Collaboration tool, Review Manager 5.3 and STATA 11.0, GRADE profiler 3.6 were used for evaluating risk of bias, analyzing, and assessing quality of evidence respectively.

RESULTS

After exclusions, 15 RCTs including a total of 1451 participants were included for analysis. We found evidence that JLT had better efficacy than CP (domperidone, omeprazole, esomeprazole, mosapride, lansoprazole, compound digestive enzymes, lactasin tablets) for FD (OR 0.34; 95% CI 0.26, 0.45; P < .00001). Moreover, JLT had more improvement on symptoms including abdominal pain, abdominal distention, early satiety, belching, poor appetite, and fatigue compared with CP. In addition, serious adverse events were not observed in treatment courses.

CONCLUSION

This meta-analysis suggested that JLT appears to have better efficacy in treating FD compared with CP. It may be an effective and safe therapy option for patients with FD. Though, more large-sample and strictly designed RCTs are needed to confirm our findings.PROSPERO registration number: CRD42019133241.

The effect of Xiang-Sha-Liu-Jun-Zi tang (XSLJZT) on irritable bowel syndrome: A randomized, double-blind, placebo-controlled trial

BACKGROUND

Irritable bowel syndrome (IBS) is characterized by chronic, recurrent abdominal pain or abdominal discomfort and changes in defecation habits. Xiang-Sha-Liu-Jun-Zi tang (XSLJZT) is a traditional Chinese medical formula that can modulate gastrointestinal disturbance.

PURPOSE

To investigate the therapeutic effect of XSLJZT on IBS.

MATERIALS AND METHODS

This study was designed as a double-blind, randomized, controlled preliminary study. Eighty patients with IBS were assigned to a control group (CG, 40 patients) that received oral administration of an XSLJZT 10% comparator (3.0 g three times daily) for 28 days or to a treatment group (TG, 40 patients) that received XSLJZT. The primary outcome measure was changes in scores on the Gastrointestinal System Rating Scale-IBS. The secondary outcome measures were changes in scores on the irritable bowel syndrome-quality of life (IBS-QOL) and World Health Organization-quality of life-brief.

RESULTS

A total of 63 patients completed the study (n = 31 for the CG; n = 32 for the TG). The TG were discovered to have significantly lower diarrhea scores than the CG at V2 (second assessment) compared with V1 (first assessment, baseline) (mean change ± SD: CG: 0.19 ± 1.33 vs. TG: -0.38 ± 0.91, p = 0.05). The scores for Item 28 on the IBS-quality of life (QOL) scale ("I feel frustrated that I cannot eat when I want because of my bowel problems") were lower in the CG at V3 (third assessment) compared with V1 but slightly higher in the TG (CG: -0.48 ± 0.89 vs. TG: 0.03 ± 0.65, p = 0.01).

CONCLUSION

Oral administration of XSLJZT (3.0 g) for 28 days lowered the mean diarrhea score in patients with IBS, indicating that the patients in the TG had greater diarrhea improvement than those in the CG. The present study used 10% XSLJZT as a comparator, and the different items of the Gastrointestinal System Rating Scale-IBS, IBS-QOL, and World Health Organization Quality of Life-Brief were scored separately. Therefore, the selection of an appropriate comparator or placebo and score assessment are crucial issues for future study.

Efficacy of Sida pilosa Retz aqueous extract against Schistosoma mansoni - induced granulomatous inflammation in the liver and the intestine of mice: histomorphometry and gastrointestinal motility evaluation

BACKGROUND

The macerate of Sida pilosa aerial parts is used empirically for the treatment of intestinal helminthiasis. Previous studies have shown that Sida pilosa aqueous extract (SpAE) has schistosomicidal, antioxidant, anti-inflammatory and anti-fibrotic activities in Schistosoma mansoni infection. This study was designed to evaluate the effect of SpAE on the granulomatous inflammation induced by S. mansoni in the liver and the intestine of mice by histomorphometry; as well as on the gastrointestinal motility.

METHODS

To study the effect of SpAE on the liver and intestine histomorphometry and on the gastrointestinal motility, SpAE was administered at 200 mg/kg per os to S. mansoni-infected mice for 4 weeks. Praziquantel was used as reference drug. Prior to carrying out sacrifice, a batch of mice was subjected to gastrointestinal transit evaluation with 3% charcoal meal. After sacrifying another batch of mice, we performed histological and morphometric analyses of the liver and the ileum. We measured the following: total proteins, transaminases, malondialdehyde, nitrites, superoxide dismutase, catalase and reduced glutathione. The effect of SpAE (4, 8, 16 and 32 mg/mL) on the ileum contractile activity was evaluated either in the absence or in the presence of pharmacological blockers.

RESULTS

SpAE induced a significant reduction of hepatosplenomegaly and intestine enlargement. The number of granulomas was reduced by 52.82% in the liver and 52.79% in the intestine, whereas the volume of hepatic granulomas decreased by 48.76% after SpAE treatment. SpAE also reduced (p < 0.001) the ileal muscular layer thickness. The levels of total proteins, transaminases, malondialdehyde, nitrites, superoxide dismutase, catalase and reduced glutathione were restored after treatment of infected mice with SpAE. A normalization of the gastrointestinal transit was also recorded after SpAE treatment. The effect of SpAE on intestinal motility was mediated via intracellular and extracellular calcium mobilization.

CONCLUSION

Our findings provide evidence that SpAE improves granulomatous inflammation induced by S. mansoni both in the liver and in the intestine, as well as it re-establishes normal gastrointestinal transit. SpAE may be used for the development of alternative medicine against S. mansoni infection.

Mechanistic evaluation of phytochemicals in breast cancer remedy: current understanding and future perspectives

Breast cancer is one of the most commonly diagnosed cancers around the globe and accounts for a large proportion of fatalities in women. Despite the advancement in therapeutic and diagnostic procedures, breast cancer still represents a major challenge. Current anti-breast cancer approaches include surgical removal, radiotherapy, hormonal therapy and the use of various chemotherapeutic drugs. However, drug resistance, associated serious adverse effects, metastasis and recurrence complications still need to be resolved which demand safe and alternative strategies. In this scenario, phytochemicals have recently gained huge attention due to their safety profile and cost-effectiveness. These phytochemicals modulate various genes, gene products and signalling pathways, thereby inhibiting breast cancer cell proliferation, invasion, angiogenesis and metastasis and inducing apoptosis. Moreover, they also target breast cancer stem cells and overcome drug resistance problems in breast carcinomas. Phytochemicals as adjuvants with chemotherapeutic drugs have greatly enhanced their therapeutic efficacy. This review focuses on the recently recognized molecular mechanisms underlying breast cancer chemoprevention with the use of phytochemicals such as curcumin, resveratrol, silibinin, genistein, epigallocatechin gallate, secoisolariciresinol, thymoquinone, kaempferol, quercetin, parthenolide, sulforaphane, ginsenosides, naringenin, isoliquiritigenin, luteolin, benzyl isothiocyanate, α-mangostin, 3,3'-diindolylmethane, pterostilbene, vinca alkaloids and apigenin.

Isoliquiritigenin inhibits proliferation and metastasis of MKN28 gastric cancer cells by suppressing the PI3K/AKT/mTOR signaling pathway

Isoliquiritigenin (ISL) is a flavonoid extracted from licorice root, which is known to serve important antitumor roles in numerous types of cancers; however, its effect on gastric cancer remains to be elucidated. The present study aimed to explore the roles and underlying mechanisms of ISL in MKN28 gastric cancer cells. MKN28 cell proliferation was measured using the Cell Counting Kit‑8 (CCK8) assay. A Transwell assay was used to determine the effects of ISL on the migration and invasion of MKN28 cells. Apoptosis was assessed by flow cytometry, and the expression levels of apoptosis‑, autophagy‑ and signaling pathway‑related proteins were detected by western blot analysis. The results of the CCK8 assay demonstrated that ISL significantly inhibited the proliferation of MKN28 cells (P<0.05). Transwell assays demonstrated that the migration and invasion of MKN28 cells were significantly inhibited following treatment with ISL (P<0.05). Flow cytometric analysis indicated that ISL induced apoptosis of MKN28 cells. In addition, western blot analysis revealed that the ratio of microtubule‑associated proteins 1A/1B light chain 3B (LC3)II/LC3I was upregulated, as was Beclin 1 expression; however, p62 was downregulated following ISL pretreatment, thus suggesting that ISL triggered autophagy in MKN28 cells. In addition, the phosphorylation levels of protein kinase B (AKT) and mammalian target of rapamycin (mTOR) were significantly reduced following ISL treatment. These results indicated that ISL may influence apoptosis and autophagy in MKN28 cells by suppressing the phosphoinositide 3‑kinase/AKT/mTOR signaling pathway. In conclusion, the findings of the present study suggested that ISL may inhibit MKN28 cell proliferation, migration and invasion by inducing apoptosis and autophagy, implying potential as a therapeutic agent for gastric cancer.

Isoliquiritigenin Ameliorates Indomethacin-Induced Small Intestinal Damage by Inhibiting NOD-Like Receptor Family, Pyrin Domain-Containing 3 Inflammasome Activation

Activation of the NOD-Like Receptor Family, Pyrin Domain-Containing 3 (NLRP3) inflammasome, which consists of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and pro-caspase-1, triggers pro-caspase-1 cleavage promoting the processing of pro-interleukin (IL)-1β into mature IL-1β, which is critical for the development of non-steroidal anti-inflammatory drug (NSAID)-induced enteropathy. We investigated the effects of isoliquiritigenin, a flavonoid derived from the roots of Glycyrrhiza species, on NSAID-induced small intestinal damage and the inflammasome activation. To induce enteropathy, mice were administered indomethacin by gavage with or without isoliquiritigenin pretreatment. Some mice received an intraperitoneal injection of recombinant murine IL-1β in addition to isoliquiritigenin and indomethacin. Indomethacin induced small intestinal damage and increased protein levels of cleaved caspase-1 and mature IL-1β in the small intestine. Treatment with 7.5 and 75 mg/kg isoliquiritigenin inhibited indomethacin-induced small intestinal damage by 40 and 56%, respectively. Isoliquiritigenin also inhibited the indomethacin-induced increase in cleaved caspase-1 and mature IL-1β protein levels, whereas it did not affect the mRNA expression of NLRP3, ASC, caspase-1, and IL-1β. Protection against intestinal damage in isoliquiritigenin-treated mice was completely abolished with exogenous IL-1β. NLRP3-/- and caspase-1-/- mice exhibited resistance to intestinal damage, and isoliquiritigenin treatment failed to inhibit the damage in NLRP3-/- and caspase-1-/- mice. Isoliquiritigenin prevents NSAID-induced small intestinal damage by inhibiting NLRP3 inflammasome activation.

Targeting oral cancer stemness and chemoresistance by isoliquiritigenin-mediated GRP78 regulation

Cancer stem cells (CSCs) are cells that drive tumorigenesis, contributing to metastasis and cancer recurrence as well as resistance to chemotherapy of oral squamous cell carcinomas (OSCC). Therefore, approaches to target CSCs become the subject of intense research for cancer therapy. In this study, we demonstrated that isoliquiritigenin, a chalcone-type flavonoid isolated from licorice root, exhibited more toxicity in oral cancer stem cells (OSCC-CSCs) compared to normal cells. Treatment of isoliquiritigenin not only inhibited the self-renewal ability but also reduced the expression of CSC markers, including the ALDH1 and CD44. In addition, the capacities of OSCC-CSCs to invade, metastasize and grow into a colony were suppressed by isoliquiritigenin. Most importantly, we showed that isoliquiritigenin potentiated chemotherapy along with downregulated expression of an ABC transporter that is associated with drug resistance, ABCG2. Moreover, a combination of isoliquiritigenin and Cisplatin significantly repressed the invasion and colony formation abilities of OSCC-CSCs. Our results suggested that administration of isoliquiritigenin reduced the protein expression of mRNA and membrane GRP78, a critical mediator of tumor biology. Overexpression of GRP78 reversed the inhibitory effect of isoliquiritigenin on OSCC-CSCs. Furthermore, isoliquiritigenin retarded the tumor growth in nude mice bearing OSCC xenografts. Taken together, these findings showed that isoliquiritigenin is an effective natural compound that can serve as an adjunct to chemotherapy for OSCC.

Isoliquiritigenin modulates miR-374a/PTEN/Akt axis to suppress breast cancer tumorigenesis and metastasis

Breast cancer is one of the most frightful causes of death among females worldwide. Accumulating evidence attached the importance of microRNAs negative regulation to tumorigenesis in breast cancer, suggesting novel cancer therapies targeting microRNAs modulation. Recent studies demonstrated that isoliquiritigenin could inhibit breast cancer cells proliferation and migration, but the underlying mechanism is still limited. In this study, the anti-cancer effects as well as the detailed mechanisms of isoliquiritigenin were explored. The results proved that isoliquiritigenin could negatively regulate breast cancer growth through the induction of apoptosis. We also verified the anti-cancer effect of isoliquiritigenin on migration and invasion, and identified highly expressed miR-374a as one of the main microRNAs down-regulated by isoliquiritigenin treatment in breast cancer. Further study displayed that isoliquiritigenin increased PTEN expression through the decrease of miR-374a expression to inhibit the aberrant Akt signaling. Our findings suggest isoliquiritigenin as a novel anti-cancer candidate significantly regulating miR-374a/PTEN/Akt axis in microRNA-based breast cancer therapies.

Economic Importance

The beneficial effects of liquorice in treating chills, colds, and coughs have been fully discussed in Ayurveda, as well as in the texts of ancient Egyptians, Greeks, and Romans. The plant has been prescribed for dropsy during the period of famous Hippocrates. The reason being that it was quite helpful as thirst-quenching drugs (Biondi et al. in J Nat Prod 68:1099–1102, 2005; Mamedov and Egamberdieva in Herbals and human health-phytochemistry. Springer Nature Publishers, 41 pp, 2017). No doubt, the clinical use of liquorice in modern medicine started around 1930; Pedanios Dioscorides of Anazarba (Adana), first century AD-Father of Pharmacists, mentions that it is highly effective in the treatment of stomach and intestinal ulcers. In Ayurveda, people in ancient Hindu culture have used it for improving sexual vigor.

Medicinal plants--prophylactic and therapeutic options for gastrointestinal and respiratory diseases in calves and piglets? A systematic review

BACKGROUND

Gastrointestinal and respiratory diseases in calves and piglets lead to significant economic losses in livestock husbandry. A high morbidity has been reported for diarrhea (calves ≤ 35%; piglets ≤ 50%) and for respiratory diseases (calves ≤ 80%; piglets ≤ 40%). Despite a highly diverse etiology and pathophysiology of these diseases, treatment with antimicrobials is often the first-line therapy. Multi-antimicrobial resistance in pathogens results in international accordance to strengthen the research in novel treatment options. Medicinal plants bear a potential as alternative or additional treatment. Based on the versatile effects of their plant specific multi-component-compositions, medicinal plants can potentially act as 'multi-target drugs'. Regarding the plurality of medicinal plants, the aim of this systematic review was to identify potential medicinal plant species for prevention and treatment of gastrointestinal and respiratory diseases and for modulation of the immune system and inflammation in calves and piglets.

RESULTS

Based on nine initial sources including standard textbooks and European ethnoveterinary studies, a total of 223 medicinal plant species related to the treatment of gastrointestinal and respiratory diseases was identified. A defined search strategy was established using the PRISMA statement to evaluate 30 medicinal plant species starting from 20'000 peer-reviewed articles published in the last 20 years (1994-2014). This strategy led to 418 references (257 in vitro, 84 in vivo and 77 clinical trials, thereof 48 clinical trials in veterinary medicine) to evaluate effects of medicinal plants and their efficacy in detail. The findings indicate that the most promising candidates for gastrointestinal diseases are Allium sativum L., Mentha x piperita L. and Salvia officinalis L.; for diseases of the respiratory tract Echinacea purpurea (L.) MOENCH, Thymus vulgaris L. and Althea officinalis L. were found most promising, and Echinacea purpurea (L.) MOENCH, Camellia sinensis (L.) KUNTZE, Glycyrrhiza glabra L. and Origanum vulgare L. were identified as best candidates for modulation of the immune system and inflammation.

CONCLUSIONS

Several medicinal plants bear a potential for novel treatment strategies for young livestock. There is a need for further research focused on gastrointestinal and respiratory diseases in calves and piglets, and the findings of this review provide a basis on plant selection for future studies.

Anti-osteoclastogenic activity of isoliquiritigenin via inhibition of NF-κB-dependent autophagic pathway

Previous studies, including those from our laboratory, have demonstrated that the natural flavonoid isoliquiritigenin (ISL) is a promising agent for bone destructive diseases. However, the mechanisms underlying its anti-osteoclastogenic effects are still far from clear. Here, we evaluated the potential alterations of autophagy and nuclear factor-κB (NF-κB) during anti-osteoclastogenic effects by ISL in vitro and in vivo. We observed that ISL inhibited the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and suppressed autophagic microtubule-associated protein light chain 3 (LC3)-II and Beclin 1 accumulation. ISL treatment resulted in the interruption of several specific features for autophagy in osteoclast precursors, including acidic vesicular organelle formation, LC3-II accumulation, and appearance of autophagic vacuoles. The RANKL-stimulated expression levels of autophagy-related genes and proteins also diminished in ISL-treated osteoclast precursors. The reactivation of autophagy by rapamycin almost reversed the ISL-elicited anti-osteoclastogenic effects. Interestingly, ISL inhibited the RANKL-stimulated NF-κB expression and nuclear translocation, whereas the NF-κB inhibitor Bay 11-7082 markedly suppressed the RANKL-induced autophagic activation. Consistent with the in vitro results, the administration of ISL could attenuate osteoclastogenic cathepsin K, autophagic LC3, and NF-κB expression to protect against inflammatory calvarial bone erosion in vivo. Our findings highlight the inhibition of NF-κB-dependent autophagy as an important mechanism of ISL-mediated anti-osteoclastogenic activity.

Traditional Chinese medicine Zhiqiao-Houpu herb-pair induce bidirectional effects on gastric motility in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Zhiqiao-Houpu herb-pair (ZQHPHP), composed of Fructus Aurantii (Zhiqiao [ZQ] in Chinese) and Magnolia officinalis (Houpu [HP] in Chinese), is a traditional herbal formula that has been extensively used for treating gastrointestinal motor dysfunction. The aim of the study was to evaluate the effect and possible mechanism of ZQHPHP on gastric emptying (GE) and gastric antral smooth muscle contractility (GASMC).

MATERIALS AND METHODS

This study includes four parts: (a) study of ZQHPHP's effect on GE; (b) study of ZQHPHP's effect on gastric antral smooth muscle contractility (GASMC); (c) comparing the effects of ZQHPHP, ZQ and HP on GASMC; (d) study of antagonists or agonists on ZQHPHP-induced GASMC. A test meal of Evans blue was adopted to estimate GE in rats. A polygraph was used to measure GASMC in rats.

RESULTS

The in vivo experiments demonstrated that, at the doses of 10mg/kg bw and 20mg/kg bw, ZQHPHP could promote GE. While, at the higher dose of 30 mg/kg bw, ZQHPHP delayed the GE. From the in vitro experiments we found that ZQHPHP (3-10 μg/ml) concentration-dependently increased the mean amplitude of contractions in the antral circular strip compared to untreated controls. While, in the concentration of 30 μg/ml, ZQHPHP prohibited GASMC. Besides, atropine blocked the stimulatory effect of ZQHPHP on GASMC and norepinephrine partly prohibited the stimulatory effect of ZQHPHP on GASMC, whereas isoproterenol showed no effect. From the in vitro experiment, we also found that ZQ and HP used together can synergistically increase gut motor.

CONCLUSIONS

The experiment indicated that ZQHPHP could induce bidirectional regulation on gastric motility. ZQ and HP used together can synergistically increase gut motor at a certain dosage. Lower dosage of ZQHPHP increases gastric motility, while higher dosage produces inhibition. In addition, the improvement of gastric motility by ZQHPHP is predominantly involved with muscarinic receptors and secondarily with alpha-receptors.

Pharmacological Effects of Glycyrrhiza spp. and Its Bioactive Constituents: Update and Review

The roots and rhizomes of various species of the perennial herb licorice (Glycyrrhiza) are used in traditional medicine for the treatment of several diseases. In experimental and clinical studies, licorice has been shown to have several pharmacological properties including antiinflammatory, antiviral, antimicrobial, antioxidative, antidiabetic, antiasthma, and anticancer activities as well as immunomodulatory, gastroprotective, hepatoprotective, neuroprotective, and cardioprotective effects. In recent years, several of the biochemical, molecular, and cellular mechanisms of licorice and its active components have also been demonstrated in experimental studies. In this review, we summarized the new phytochemical, pharmacological, and toxicological data from recent experimental and clinical studies of licorice and its bioactive constituents after our previous published review.

Effects of the aqueous extract of Pittosporum mannii Hook. f. (Pittosporaceae) stem barks on spontaneous and spasmogen-induced contractile activity of isolated rat duodenum

ETHNOPHARMACOLOGICAL RELEVANCE

Pittosporum mannii Hook. f. (Pittosporaceae) is a plant widely used in traditional medicine in Cameroon for the treatment of many gastrointestinal disorders including diarrhea. To date, no pharmacological study on the antidiarrheal and the antispasmodic properties of this plant has been reported. The aim of the present study was to evaluate in vitro the relaxant activity of the aqueous extract of stem barks of P. mannii (PMAE) on rat duodenum.

MATERIALS AND METHODS

Different concentrations of PMAE were tested separately (10-80 µg/mL) or cumulatively (5-80 µg/mL) on spontaneous and spasmogen (carbachol, histamine and KCl)-induced contractions of isolated rat duodenum strips.

RESULTS

At concentrations ranging from 10 to 80 µg/mL, PMAE significantly decreased the tonus and the amplitude of spontaneous contractions. However, at high concentration (80 µg/mL), the extract elicited a transient relaxation was followed by a slight increase of tonus, while the amplitude remained lower compared to the normal spontaneous activity. The relaxant effect of the extract was not significantly affected in the presence of atropine (0.713 µg/mL) and promethazine (0.5 µg/mL). In addition, PMAE (20, 40, and 80 µg/mL) partially but significantly inhibited in a concentration related manner the contractions induced by carbachol (10(-9)-10(-4)M) and histamine (10(-9)-10(-4)M) on rat duodenum. PMAE (10-80 µg/mL) also significantly induced a concentration-dependent relaxation on KCl (20mM, 50mM, 10(-3)-6.10(-3)M)-induced contraction of rat duodenum.

CONCLUSIONS

These results show that the aqueous extract of P. mannii stem barks possesses antispasmodic and spasmolytic effects at lower concentrations; therefore, supporting the use of the stem barks of this plant in the folk medicine for the treatment of diarrhea. However, caution should be paid while using higher concentrations that instead might produce spasmogenic effect and might worsen the diarrheal condition. The relaxant effect of PMAE appears to be non-specific of muscarinic or histaminic receptors, but may involve at least in part a mechanism of inhibition of the Ca(2+) influx into the smooth muscle cells through voltage-operated Ca(2+) channels.

Effect of Sijunzi decoction and its active substances on gastrointestinal motility

Sijunzi decoction (SJZD), earliest recorded in Taiping Huimin Heji Ju Fang, is a classic recipe for the therapy of spleen deficiency. The recipe consists of merely four kinds of traditional Chinese herbs (ginseng, rhizoma atractylodis macrocephalae, poria cocos and licorice), but it has wide clinical applications and good efficacy, especially in the treatment of gastrointestinal function. It is reported that each component of the SJZD has different effects on gastrointestinal movement. Experimental studies have shown that SJZD has bidirectional modulatory effects on gastrointestinal motility and can therefore treat gastrointestinal movement dysfunction.

An integrated exact mass spectrometric strategy for comprehensive and rapid characterization of phenolic compounds in licorice

RATIONALE

Licorice (Gancao) is derived from the dried roots and rhizomes of Glycyrrhiza species (Leguminosae) and appears as a component herb in about 60% of traditional Chinese medicine (TCM) prescriptions. Modern pharmacological studies have shown that flavonoids are one class of the major components responsible for the bioactivities of licorice. Ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/QTOF MS) has proven to be a powerful tool for rapid profiling and identification of natural products in complex herbal medicines.

METHODS

A UPLC/QTOF MS method was established for the first time for profiling and structural characterization of the phenolic compounds (most of them flavonoids) in licorice. The combined use of data-independent acquisition (MS(E) ) and data-dependent acquisition (DDA) was illustrated.

RESULTS

Fifteen flavonoid reference compounds were used to explore the fragmentation pathways. Compound identification was based upon the exact mass, general fragmentation behaviors, retention times, UV absorption, and the related botanical biogenesis. As a result, a total of 51 compounds were characterized, three of which were reported for the first time.

CONCLUSIONS

The LC/MS analysis for each injection took less than 9 min. The developed method is fast, accurate and reliable due to its high resolution and high efficiency characteristics as a result of combining both UPLC separation and QTOF exact mass measurement.

Pharmacokinetic comparisons of two different combinations of Shaoyao-Gancao Decoction in rats: competing mechanisms between paeoniflorin and glycyrrhetinic acid

ETHNOPHARMACOLOGICAL RELEVANCE

Shaoyao-Gancao Decoction (SGD), a well-known traditional Chinese medicine prescription, is a combination of Radix Paeoniae Alba (Paeonia lactiflora Pall, root) and Glycyrrhizae uralensis (Glycyrrhiza uralensis Fisch., root and rhizome, honeyed) for spasmolysis and emergency pain relief. Paeoniflorin (PF) and glycyrrhetinic acid (GA) are two typical active components of SGD for pain relief.

AIM OF THE STUDY

To study comparative pharmacokinetics of ten bioactive compounds in SGDs with two different combinations of RP and GU, and therefore to investigate the herb-herb interaction mechanisms of Shaoyao-Gancao Decoction for better spasmolysis and emergency pain relief in rats.

MATERIALS AND METHODS

Herbal IR macro-fingerprinting was implemented to provide the full chemical fingerprints of RP, GU and SGD decoctions and to investigate the variation rule of the full chemical profile of SGDs with various combinations of RP and GU. A specifically developed HPLC-MS/MS assay coupled with protein precipitation method was employed to determine the plasma concentrations of the ten analytes. Male Wistar rats were orally administered with SGD1 (RP:GU, 1:1 (w/w)) and SGD2 ((RP:GU, 4:1 (w/w)) equivalent to 9.5 g/kg body weight of GU.

RESULTS

Full chemical fingerprints of RP, GU and SGDs with various combinations of RP and GU were provided in the form of IR macro-fingerprints. Except for liquiritin, there were statistically significant differences (p<0.05 or p<0.01) of these analytes between SGD1 and SGD2 in in vivo pharmacokinetic study. Compared with the results when oral administrated with SGD1, six glycosides (PF, albiflorin, oxypaeoniflorin, isoliquiritin, ononin, and glycyrrhizin) exhibited higher systematic exposure levels (AUC0-t) and slower elimination rates (CL) whereas two glycones (GA and isoliquiritigenin) were the reverse when administrated with SGD2.

CONCLUSIONS

Increasing the amount of RP attenuated the inhibitory effect of GA via competing being consumed by intestinal bacteria (or β-glucosidase) to reduce the conversion amount of glycyrrhizin to GA and subsequently to afford significantly higher bioavailability and longer efficacy of PF, glycyrrhizin, albiflorin, oxypaeoniflorin, isoliquiritin, and ononin, leading to better spasmolysis and emergency pain relief.

Isoliquiritigenin enhances radiosensitivity of HepG2 cells via disturbance of redox status

Redox balance plays an important role in the maintenance of cell growth and survival. Disturbance of this equilibrium can alter normal cellular processes. Excessive reactive oxygen species (ROS) are often found in cancer cells. However, cancer cells have an efficient antioxidant system to counteract the increased generation of ROS. This high antioxidant capacity also favors resistance to drugs and radiation. Here, we show that isoliquiritigenin (ISL), a natural antioxidant, effectively decreased ROS in HepG2 cells in a time-dependant manner at 0.5, 1, and 2 h of treatment. The decreased ROS caused redox imbalance and reductive stress. To adapt to this state, nuclear factor erythroid-2-related factor 2, which regulates the antioxidant enzyme system, was significantly decreased. Antioxidant enzymes reached their lowest level at 6 h after ISL treatment. Endogenous ROS were still being generated so after 6 h of ISL treatment, ROS were clearly higher than before ISL treatment, causing redox imbalance in the HepG2 cells which changed from reductive to oxidative stress. At this stage, cells were irradiated with X-rays. The excess ROS induced serious oxidative stress, resulting in radiosensitization. Therefore, we concluded that ISL induced oxidative stress by disturbing the redox status and ultimately enhancing the radiosensitivity of HepG2 cells.

Pharmacokinetic comparisons of different combinations of Shaoyao-Gancao-Decoction in rats: simultaneous determination of ten active constituents by HPLC-MS/MS

A specific HPLC-MS/MS method was developed and validated for simultaneous determination of ten constituents including albiflorin, oxypaeoniflorin, paeoniflorin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, ononin, glycyrrhizin and glycyrrhetinic acid in rat plasma using genistein as an internal standard (IS). The rat plasma samples were prepared by a one-step direct protein precipitation procedure with methanol. HPLC separation was achieved on a Zorbax XDB-C18 column (2.1mm×50mm i.d., 3.5μm) with gradient elution (A: 0.1% aqueous formic acid; B: methanol with 0.1% formic acid) at a flow rate of 0.5mL/min in a run time of 7min. All analytes and IS were detected by multiple reaction monitoring scanning with electrospray ionization in the negative ion mode. Calibration curves showed good linearity (r>0.998) over a wide concentration range for all analytes. The intra- and inter-day precisions were all within 15% and the accuracies were in the range of -6.2% to 10.1%. The validated method was successfully applied to determination and comparative pharmacokinetics investigation of the ten constituents in rat plasma after oral administration of different combinations (Radix Paeoniae Alba:Glycyrrhiza uralensis=1:1 or 4:1) of Shaoyao-Gancao-Decoction (SGD) extracts. Pharmacokinetic parameters were evaluated by a compartment model. There were perceptible differences in pharmacokinetic parameters (Cmax, AUC0-t, CL) of the analytes except for liquiritin between the two groups of SGD.

Antispasmodic effect of shakuyakukanzoto extract on experimental muscle cramps in vivo: role of the active constituents of Glycyrrhizae radix

ETHNOPHARMACOLOGICAL RELEVANCE

Shakuyakukanzoto (SKT) composed of Glycyrrhizae radix (G. radix) and Paeoniae radix (P. radix) has been traditionally used in Japan, Korea and China as an antispasmodic drug for the treatment of skeletal muscle cramps and intestinal cramps.

AIM OF THIS STUDY

To evaluate the antispasmodic activity of SKT and its two components, as well as to identify the key constituents of the components which mediate this effect in skeletal muscles in vivo.

MATERIALS AND METHODS

An experimental cramp model was constructed to evaluate the effects of peripherally-acting muscle relaxants on electrically-induced cramps under physiological conditions. This was accomplished by surgically isolating the motor supply to the gastrocnemius muscle in an anesthetized rat and delivering electrical stimuli to an isolated tibial nerve to induce tetanic contractions. We first tested dantrolene, a well-known peripherally-acting relaxant, to determine the sensitivity and reliability of our experimental model. We then evaluated the effects of SKT, P. radix, G. radix, and the eight active constituents of G. radix against tetanic contractions.

RESULTS

We found that dantrolene (10 and 30 mg/kg, i.d.) rapidly and significantly inhibited tetanic contractions (P<0.01) irrespective of dose. SKT (0.5, 1.0, and 2.0 g/kg, i.d.) and G. radix (0.5 and 1.0 g/kg, i.d.) also significantly inhibited tetanic contractions (P<0.01) but in a dose-dependent manner owing to the actions of six of the eight active constituents in G. radix (liquiritin apioside, liquiritigenin, isoliquiritin apioside, isoliquiritigenin, glycycoumarin, and glycyrrhetinic acid, 20 μmol/kg, i.v.). These constituents, which include flavonoids, a triterpenoid, and a courmarin derivative, demonstrated temporal variations in their inhibitory activity. In contrast, P. radix (0.5 and 1.0 g/kg, i.d.) did not show a statistically significant antispasmodic effect in our study; however, we previously found that it had a significant antinociceptive effect.

CONCLUSIONS

Our findings show that SKT inhibits tetanic contractions in vivo and that G. radix is the main antispasmodic component due to the actions of its active constituents, thus supporting the traditional use of SKT. We further propose that SKT containing the antispasmodic G. radix and antinociceptive P. radix is a pharmaceutically elegant option for muscle cramps as treatment requires a two-pronged approach, i.e., inhibition of hyperexcitable skeletal tissues and modulation of the pain accompanying cramps.

Chinese herbal medicine liu jun zi tang and xiang sha liu jun zi tang for functional dyspepsia: meta-analysis of randomized controlled trials

Objectives. To assess the efficacy and safety of Liu Jun Zi Tang (LJZT) and Xiang Sha Liu Jun Zi Tang (XSLJZT) for treating functional dyspepsia. Methods. Literature searches were carried out on Medline database, Cochrane Library, CNKI database, Chinese Biomedical Literature database, Wanfang database, and VIP database up to July 2012. Hand search for further references was conducted. Study selection, data extraction, quality assessment, and data analyses were performed according to the Cochrane standards. Results. Fifteen publications in total were suitable for inclusion. There was evidence that LJZT compared with prokinetic drugs increased symptom improvement (odds ratio 1.96, 95% CI 1.15 to 3.36). There was also evidence that XSLJZT compared with prokinetic drugs increased symptom improvement (odds ratio 2.63, 95% CI 1.72 to 4.03). No adverse events were reported in LJZT or XSLJZT group in any of these randomized controlled trials. Conclusion. LJZT and XSLJZT might be more effective compared with prokinetic drugs in the treatment of functional dyspepsia, and no side effects are identified in the included trials. However, due to poor methodological quality in the majority of included studies, the potential benefit from LJZT and XSLJZT need to be confirmed in rigorously designed, multicentre, and large-scale trials.

Mammalian target of rapamycin regulates isoliquiritigenin-induced autophagic and apoptotic cell death in adenoid cystic carcinoma cells

Previous studies, including those from our laboratory, have demonstrated that isoliquiritigenin (ISL), a flavonoid isolated from licorice, is a promising cancer chemotherapeutic agent. However the mechanisms underlying its anticancer effects are still far from clear. We now show, for the first time, that ISL triggers the mammalian target of rapamycin (mTOR)-dependent autophagic and apoptotic cell death in adenoid cystic carcinoma (ACC). Exposure of both ACC-2 and ACC-M cells to ISL resulted in several specific features for autophagy, including the appearance of membranous vacuoles, formation of acidic vesicular organelles, punctate pattern of LC3 immunostaining, and an increase in autophagic flux. Moreover, ISL treatment also resulted in significantly increased apoptosis in ACC cells. The ISL-mediated autophagic and apoptotic cell death were obviously attenuated by transfection with dominant negative Atg5 (DN-Atg5(K130R)) plasmids or treatment with 3-methyladenine(3-MA). In additon, the data also revealed that the autophagic and apoptotic cell death induced by ISL occurred through a mTOR-dependent pathway. More importantly, the xenograft model using ACC-M cells provided further evidence of the occurrence of ISL-induced autophagy and apoptosis in vivo, correlating with the suppresson of mTOR activation as well as up-regulation of Atg5 expression. Taken together, these findings in our study suggest that induction of mTOR-dependent autophagic and apoptotic cell death may be an important mechanism in cancer chemotherapy by ISL.

Inhibitory effects of indicaxanthin on mouse ileal contractility: analysis of the mechanism of action

Recently, we have showed that indicaxanthin, the yellow betalain pigment abundant in the fruit of Opuntia ficus indica, has remarkable spasmolytic effects on the intestinal contractility in vitro. Thus, the purpose of the present study was to investigate the mechanism of action underlying the observed response. We used organ bath technique to record the mechanical activity of the mouse ileum longitudinal muscle and ELISA to measure the levels of cAMP. Indicaxanthin induced inhibitory effects on spontaneous mechanical activity, which were unaffected by indomethacin, a non-selective inhibitor of cycloxygenase; 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a selective inhibitor of nitric oxide-dependent guanylyl cyclase; 2'5'dideoxyadenosine, an adenylyl cyclase inhibitor; and zaprinast, a selective inhibitor of the cGMP phosphodiesterase isoenzyme. Indicaxanthin effects were reduced significantly in the presence of 3-isobutyl-1-methylxanthine (IBMX), a non selective inhibitor of phosphodiesterases (PDEs). Indicaxanthin and IBMX significantly reduced the carbachol-evoked contractions and the joint application of both drugs did not produce any additive effect. Indicaxanthin and IBMX increased the inhibitory effects of forskolin, an adenylyl cyclase activator, and the joint application of both drugs did not produce any additive effect. Indicaxanthin, contrarily to IBMX, did not affect the inhibitory action of sodium nitroprusside, a soluble guanylyl cyclase activator. Indicaxanthin increased both basal and forskolin-induced cAMP content of mouse ileal muscle. The present data show that indicaxanthin reduces the contractility of ileal longitudinal muscle by inhibition of PDEs and increase of cAMP concentration and raise the possibility of using indicaxanthin in the treatment of motility disorders, such as abdominal cramps.

Antispasmodic and antioxidant activities of fractions and bioactive constituent davidigenin isolated from Mascarenhasia arborescens

ETHNOPHARMACOLOGICAL RELEVANCE

Mascarenhasia arborescens A. DC. (Apocynaceae) is used in traditional medicine in the North of Madagascar to treat intestinal disorders, intestinal spasms and diarrhoea.

AIM OF THE STUDY

The main objective of this work was to evaluate the antispasmodic activity of the crude methanolic extract of Mascarenhasia arborescens and of its four partitions and to identify the effective compound responsible for this effect.

MATERIALS AND METHODS

Isolation and structure elucidation techniques were performed in order to identify the bioactive constituent of Mascarenhasia arborescens and HPLC analysis was used for its quantification. Total phenolic content (TPC) of crude extracts and partitions were determined using the Folin-Ciocalteu method. Crude methanolic extract, partitions and the bioactive compound were investigated for their spasmolytic activity on several isolated organs. Their antiradical activity was also investigated by the DPPH test.

RESULTS

Bioassay-guided fractionation using isolated guinea pig ileum pre-contracted with histamine 3x10(-6) M led to the isolation of davidigenin (DG), a dihydrochalcone, as the main active constituent from the most promising methylene chloride partition (McP). This partition was effective on isolated guinea pig ileum pre-contracted with 3x10(-6) M histamine, with a median effective concentration (EC(50)) of 41.19+/-3.74 microg/ml. The DG content of this partition was shown to be 26.5% by HPLC. DG induced a concentration-dependent relaxation of the histamine pre-contracted guinea pig ileum with an EC(50) of 8.04+/-0.81 microg/ml and a concentration-dependent relaxation of the acetylcholine pre-contracted rat duodenum with an EC(50) of 9.35+/-0.30 microg/ml. It inhibited in a non-competitive manner histamine-induced isolated ileum contraction and the acetylcholine-induced isolated duodenum contraction. Moreover, DG does not have any antiradical activity.

CONCLUSIONS

We demonstrated for the first time antispasmodic and antioxidant effects of Mascarenhasia arborescens. This study supports its use in traditional medicine. Furthermore, we highlighted the crucial role of davidigenin in the antispasmodic activity of this plant.