Herb-drug interactions between Scutellariae Radix and mefenamic acid: Simultaneous investigation of pharmacokinetics, anti-inflammatory effect and gastric damage in rats

Efficacy identification and active compounds screening of topically administration of Scutellaria Radix in oral ulcer

Scutellaria Radix (SR) is often added to various preparations for the treatment of oral ulcer, but its own efficacy and active compounds are still unknown while topically administration for oral ulcer, bring obstacles in further research. We expected to demonstrate the anti-oral ulcer effect of SR and find out its hallmark compounds, so as to provide reference for its material basis research. In this study, in vivo and in vitro models were used to prove the efficacy of SR, and spectrum-effect analysis was used to figure out the active compounds. In oral ulcer rats, SR significantly reduced TNF-α and IL-8 level, raised IL-2 level in both serum and mucosa, enhanced SOD activity and decreased MDA level of serum, reduced inflammatory reaction and showed good therapeutic effect. As for in vitro models, SR increased the survival rates of H₂O₂ damaged HOK, inhibited the release of IL-1β and NO of LPS induced HOK and LPS induced RAW 264.7, demonstrating good efficacy on oral ulcer. Subsequently, fingerprints and cellular pharmacodynamic data for 18 batches of SR were acquired, and spectrum-effect analysis were carried out by grey correlation analysis (GRA), partial least squares regression (PLSR) and "spider-web" mode. Five potential compounds were screened out and validated by comparing with SR activity, and baicalin, baicalein, and wogonoside were finally identified as active compounds of SR. These results explained the material basis of SR in treating oral ulcer and provided a scientific evidence for the clinical application of SR in oral administration.

Drug-herb interactions between Scutellaria baicalensis and pharmaceutical drugs: Insights from experimental studies, mechanistic actions to clinical applications

Whilst the popular use of herbal medicine globally, it poses challenges in managing potential drug-herb interaction. There are two folds of the drug-herb interaction, a beneficial interaction that may improve therapeutic outcome and minimise the toxicity of drug desirably; by contrast, negative interaction may evoke unwanted clinical consequences, especially with drugs of narrow therapeutic index. Scutellaria baicalensis Georgi is one of the most popular medicinal plants used in Asian countries. It has been widely used for treating various diseases and conditions such as cancer, diabetes, inflammation, and oxidative stress. Studies on its extract and bioactive compounds have shown pharmacodynamic and pharmacokinetic interactions with a wide range of pharmaceutical drugs as evidenced by plenty of in vitro, in vivo and clinical studies. Notably, S. baicalensis and its bioactives including baicalein, baicalin and wogonin exhibited synergistic interactions with many pharmaceutical drugs to enhance their efficacy, reduce toxicity or overcome drug resistance to combat complex diseases such as cancer, diabetes and infectious diseases. On the other hand, S. baicalensis and its bioactives also affected the pharmacokinetic profile of many drugs in absorption, distribution, metabolism and elimination via the regulatory actions of the efflux pumps and cytochrome P450 enzymes. This review provides comprehensive references of the observed pharmacodynamic and pharmacokinetic drug interactions of Scutellaria baicalensis and its bioactives. We have elucidated the interaction with detailed mechanistic actions, identified the knowledge gaps for future research and potential clinical implications. Such knowledge is important for the practice of both conventional and complementary medicines, and it is essential to ensure the safe use of related herbal medicines. The review may be of great interest to practitioners, consumers, clinicians who require comprehensive information on the possible drug interactions with S. baicalensis and its bioactives.

Medicinal Plants in the Treatment of Peptic Ulcer Disease: A Review

Peptic Ulcer Disease (PUD) is the most common disorder of the stomach and duodenum, which is associated with Helicobacter pylori infection. PUD occurs due to an imbalance between offensive and defensive factors and Proton Pump Inhibitors (PPI), Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and antibiotics are frequently used for the treatment. Recently, medicinal plants have emerged as efficacious, safe and widely available alternative therapies for PUD. The aim of this review was to study the medicinal plants and phytochemicals, which have been used for PUD treatment to evaluate the potential role of natural compounds to develop herbal remedies for PUD. Information was obtained using a literature search of electronic databases, such as Web of Science, Google Scholar, PubMed, Sci Finder, Reaxys and Cochrane. Common and scientific names of the plants and keywords such as 'peptic ulcer', 'gastric ulcer', 'stomach ulcer' and 'duodenal ulcer' were used for search. Eventually, 279 plants from 89 families were identified and information on the plant families, part of the plant used, chemical constituents, extracts, ulcer model used and dosage were abstracted. The results indicated that most of the anti-PUD plants were from Asteraceae (7.1%) and Fabaceae (6.8%) families while flavonoids (49%), tannins (13%), saponins (10%) and alkaloids (9%) were the most common natural compounds in plants with anti-PUD activity.

Synergistic anti-inflammatory effects of silibinin and thymol combination on LPS-induced RAW264.7 cells by inhibition of NF-κB and MAPK activation

BACKGROUND

Combination drug therapy has become an effective strategy for inflammation control. The anti‑inflammatory capacities of silibinin and thymol have each been investigated on its own, but little is known about the synergistic anti-inflammatory effects of these two compounds.

PURPOSE

This study aims to investigate the synergistic anti-inflammatory effects of silibinin and thymol when administered in combination to lipopolysaccharide (LPS)-induced RAW264.7 cells.

METHODS

RAW264.7 cells were pre-treated with silibinin and thymol individually or in combination for 2 h before LPS stimulation. Cell viability was detected by the MTT assay. Nitric oxide (NO) production was measured by Griess reagent. Reactive oxygen species (ROS) was evaluated by 2',7'-dichlorofluorescein-diacetate. ELISA was used to detect tumour necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Western blot was performed to analyse the protein expression of LPS-induced RAW264.7 cells.

RESULTS

We observed a synergistic anti-inflammatory effect of silibinin and thymol when administered in combination to LPS-induced RAW264.7 cells. Silibinin combined with thymol (40 μM and 120 μM respectively, with the molar ratio 1:3) had more potent effects on the inhibition of NO, TNF-α, and IL-6 than those exerted by individual administration of these compounds in LPS-induced RAW264.7 cells. The combination of silibinin and thymol (40 μM and 120 μM respectively, with the molar ratio 1:3) strongly inhibited ROS and cyclooxygenase-2 (COX-2). More importantly, the combination of silibinin and thymol (40 μM and 120 μM respectively, with the molar ratio 1:3) was also successful in inhibiting nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) activities. Our results suggest that the synergistic anti-inflammatory effects of silibinin with thymol were associated with the inhibition of NF-κB and MAPK signalling pathways.

CONCLUSION

The combination of silibinin and thymol (40 μM and 120 μM, respectively, with the molar ratio 1:3) could inhibit inflammation by suppressing NF-κB and MAPK signalling pathways in LPS-induced RAW264.7 cells.

Oroxyloside ameliorates acetaminophen-induced hepatotoxicity by inhibiting JNK related apoptosis and necroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Oroxyloside is a natural flavonoid isolated from Scutellaria baicalensis Georgi (Lamiaceae) which is a Chinese herb widely used for liver diseases. However, its mechanisms on protecting against drug induced liver injury has not been investigated yet.

AIM OF THE STUDY

To investigate the protecting effects and the primary mechanisms of oroxyloside on acetaminophen (APAP)-induced liver injury.

MATERIALS AND METHODS

After a 12 h fasting period with free access to water, C57BL/6 mice were injected with APAP (300 mg/kg) intragastrically (i.g.) and 1 h later with oroxyloside (100 mg/kg, i.g.). When mice sacrificed, blood samples were collected from fundus venous plexus and liver tissues were collected. In addition, cells were incubated with 10 mM APAP alone and 10 mM APAP combined with 100 μM oroxyloside for 24 h. ELISA, TUNEL assay, qRT-PCR et al. were used to assess the effect of oroxyloside on ameliorating APAP-induced hepatotoxicity in vitro and in vivo. Western bolt and immunohistochemistry were used in the signaling pathway analysis.

RESULTS

Oroxyloside administration significantly decreased the accumulations of CYP2E1, CYP1A2, IL-6, IL-1β, ALT and AST induced by APAP in vivo. In addition, oroxyloside inhibited the APAP-induced JNK related apoptosis by enhancing the antioxidant defenses, reversing ER-stress and keeping the mito-balance of liver cells in vivo and in vitro. Furthermore, oroxyloside protected the liver cells from necroptosis by affecting JNK pathway.

CONCLUSION

Oroxyloside acted as a protective agent against APAP-induced liver injury through inhibiting JNK-related apoptosis and necroptosis.

Combination use of tolfenamic acid with curcumin improves anti-inflammatory activity and reduces toxicity in mice

Long-term use of tolfenamic acid inevitably causes side effects, including gastric ulcer and hepatotoxicity. Curcumin is generally recognized to be anti-inflammatory, hepatoprotective, and gastroprotective. Herein, we investigated the combinational effects of tolfenamic acid and curcumin and possible mechanism in a TPA-induced inflammation mouse model. Combinational use of tolfenamic acid (100 mg/kg) and curcumin (100 mg/kg) by oral administration reduced dermal inflammation represented by ear edema and lymphocytic infiltration. Moreover, curcumin dispersed in polyvinyl pyrrolidone showed stronger synergistic effect. The beneficial effect of the coadministration was also reproduced in PKC/Akt/IKK/NF-κB signaling pathways. Notably, hepatoprotective and gastroprotective effect was exhibited by the reverse of body weight loss and NF-κB downregulation in the liver, and by increased Spleen Index of mice. These results suggested combination administration of tolfenamic acid with curcumin enhances anti-inflammatory efficacy and reduces hepatic/gastric toxicity, which indicates dietary uptake of curcumin may facilitate the function of tolfenamic acid. PRACTICAL APPLICATIONS: Curcumin, a representative polyphenolic compound, is one of the main constituents of dietary spice turmeric which has been widely consumed throughout the world, especially in Asia. The beneficial aspect of combination use of curcumin in enhancing anti-inflammatory effect and reducing hepatic/gastric toxicity of NSAID drug tolfenamic acid in mice has been explored. It might be anticipated as a potential naturally derived bioactive constituent in functional food and pharmaceutical applications.

Combined effects of Scutellaria baicalensis with metformin on glucose tolerance of patients with type 2 diabetes via gut microbiota modulation

Metformin is a widely prescribed antidiabetic agent, whereas Scutellaria baicalensis (SB) is a commonly used medicinal herb for treatment of type 2 diabetes (T2D). Gut microbiota is involved in pathophysiology of metabolic diseases including T2D, and intestinal microbiota may be one of the important therapeutic targets for the ailment. This study was conducted to investigate the effects of SB combined with metformin on treatment of T2D while evaluating changes in the gut microbiota composition. Patients with T2D were randomized into control and treatment groups. Subjects who had already been prescribed metformin were allotted to additional SB (3.52 g/day) group or placebo group. The initial treatment session was 8 wk, and after washout period for 4 wk they were crossed over to the opposite treatment for another 8 wk. The influence of SB and placebo on the intestinal microbiota was analyzed by MiSeq system based on 16S rRNA gene. Glucose tolerance was lower in the SB group than the placebo group. Similarly, the relative RNA expression of TNF-α was significantly reduced after SB treatment. SB treatment influenced the gut microbiota, especially Lactobacillus and Akkermansia, which showed remarkable increases after SB treatment. Some subjects showed high liver enzyme levels after SB treatment, and their microbiota composition at baseline differed with subjects whose liver enzymes were not affected. We also predicted that selenocompound metabolism was increased and naphthalene degradation was decreased after SB treatment. These results suggest that SB with metformin treatment may improve the glucose tolerance and inflammation and influence the gut microbiota community in T2D.

Unraveling the Molecular Mechanism of Traditional Chinese Medicine: Formulas Against Acute Airway Viral Infections as Examples

Herbal medicine, including traditional Chinese medicine (TCM), is widely used worldwide. Herbs and TCM formulas contain numerous active molecules. Basically, they are a kind of cocktail therapy. Herb-drug, herb-food, herb-herb, herb-microbiome, and herb-disease interactions are complex. There is potential for both benefit and harm, so only after understanding more of their mechanisms and clinical effects can herbal medicine and TCM be helpful to users. Many pharmacologic studies have been performed to unravel the molecular mechanisms; however, basic and clinical studies of good validity are still not enough to translate experimental results into clinical understanding and to provide tough evidence for better use of herbal medicines. There are still issues regarding the conflicting pharmacologic effects, pharmacokinetics, drug interactions, adverse and clinical effects of herbal medicine and TCM. Understanding study validation, pharmacologic effects, drug interactions, indications and clinical effects, adverse effects and limitations, can all help clinicians in providing adequate suggestions to patients. At present, it would be better to use herbs and TCM formulas according to their traditional indications matching the disease pathophysiology and their molecular mechanisms. To unravel the molecular mechanisms and understand the benefits and harms of herbal medicine and TCM, there is still much work to be done.

Pharmacokinetics of B-Ring Unsubstituted Flavones

B-ring unsubstituted flavones (of which the most widely known are chrysin, baicalein, wogonin, and oroxylin A) are 2-phenylchromen-4-one molecules of which the B-ring is devoid of any hydroxy, methoxy, or other substituent. They may be found naturally in a number of herbal products used for therapeutic purposes, and several have been designed by researchers and obtained in the laboratory. They have generated interest in the scientific community for their potential use in a variety of pathologies, and understanding their pharmacokinetics is important for a grasp of their optimal use. Based on a comprehensive survey of the relevant literature, this paper examines their absorption (with deglycosylation as a preliminary step) and their fate in the body, from metabolism to excretion. Differences among species (inter-individual) and within the same species (intra-individual) variability have been examined based on the available data, and finally, knowledge gaps and directions of future research are discussed.

Impact of the Chinese herbal medicines on dual antiplatelet therapy with clopidogrel and aspirin: Pharmacokinetics and pharmacodynamics outcomes and related mechanisms in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Dual antiplatelet therapy (DAPT) with aspirin (ASA) and clopidogrel (CLP) has been consistently shown clinical effectiveness in patients with coronary artery disease. According to the literature, four traditional Chinese medicine (TCM) herbs effective for prevention cardiovascular diseases, namely Radix Salvia Miltiorrhiza (Red sage root, Danshen), Radix Pueraria Lobata (Kudzu root, Gegen), Radix Angelica Sinensis (Angelica root, Danggui), and Rhizoma Ligusticum chuanxiong (Szehuan lovage rhizome, Chuanxiong), are of high potential to be co-administered during DAPT. Since all these herbs are blood vitalizing medicines and can promote blood circulation and eliminate blood stasis, it was hypothesized that they may potentially alter the clinical outcomes of DAPT with clopidogrel and aspirin.

AIM OF STUDY

The current study is proposed aiming to preliminarily evaluate the impact of these four commonly used Chinese medicinal herbs on the pharmacokinetics and pharmacodynamics of the combination therapy with clopidogrel and aspirin and its relevant outcomes and mechanisms.

MATERIALS AND METHODS

In order to mimic the standard dosing regimen for DAPT in human, various Sprague-Dawley rats treatment groups were received a bolus oral dose of DAPT on day 1 followed by DAPT for consecutive 13 days in absence and presence of orally co-administered four TCM herbs (Danshen, Gegen, Danggui and Chuanxiong) at their low and high doses. On day 14, serial blood samples were collected after dosing to obtain the plasma concentrations of ASA, CLP and their corresponding metabolites by LC/MS/MS. At the end of last blood sampling point of each rat, about 4.5 ml of whole blood were collected to estimate the prothrombin time from each treatment groups. After all the blood sampling, the rats were sacrificed followed by collecting their livers for evaluations of enzyme activities and expressions in the related liver microsome preparations and stomach tissues for evaluations of their potential ulcer index. In addition, gene expression and protein levels of related biomarkers (COX-1, COX-2, P2Y12) in rat livers were measured by RT-PCR and Western blot, respectively, and compared among different treatment groups.

RESULTS

Co-administration of Gegen and Danggui significantly altered the pharmacokinetics of ASA and CLP in DAPT with increased systemic exposure of ASA and CLP respectively. Although minimal impact on aspirin esterase activity for all co-administered herbs, significant inhibition on rCyp2c11 and carboxylesterase activities were observed for DAPT with Danshen, Gegen and Danggui co-treatment. In addition, significantly longer PT were found in all DAPT treatment groups. However, a trend of decrease in PT of DAPT in presence of Gegen, Danggui and Chuanxiong was noticed. Nevertheless, all the treatments did not cause detectable changes in COX and P2Y12 mRNA and protein expressions.

CONCLUSION

Among the four studied TCMs, it was demonstrated that co-administration of Gegen and Danggui could lead to altered pharmacokinetics of DAPT with significant inhibition on rCyp2c11 and carboxylesterase activities. Although Gegen, Danggui and Chuanxiong might potentially offset the anticoagulant activity of DAPT, the overall pharmacodynamics outcome was not considered to be harmful due to lack of risk in bleeding, which warrant further verification for its clinical impact.

Flavonoids are identified from the extract of Scutellariae Radix to suppress inflammatory-induced angiogenic responses in cultured RAW 264.7 macrophages

Scutellariae Radix (SR), also named Huangqin in China, is the dried root of Scutellaria baicalensis Georgi. Historically, the usage of SR was targeted to against inflammation. In fact, chronic inflammation has a close relationship with hypoxia and abnormal angiogenesis in tumor cells. Hence, we would like to probe the water extract of SR in suppressing the inflammation-induced angiogenesis. Prior to determine the pharmaceutical values of SR, the first step is to analysis the chemical compositions of SR according to China Pharmacopeia (2015). From the results, the amount of baicalin was 12.6% by weight. Furthermore, the anti-angiogenic properties of SR water extract were evaluated in lipopolysaccharide (LPS) pre-treated cultured macrophage RAW 264.7 cells by detecting the inflammatory markers, i.e. Cox-2, cytokine and iNOS, as well as the translocation activity of NFκB and angiogenic biomarker, i.e. VEGF. This herbal extract was capable of declining both inflammatory and angiogenic hallmarks in a concentration-dependent manner. Moreover, the SR-derived flavonoids, i.e. baicalin, baicalein, wogonin and wogonoside, were shown to be active chemicals in the anti-inflammatory-induced angiogenesis. Therefore, the inflammation-induced angiogenesis is believed to be suppressed by SR water extract, or its major ingredients. These results shed light in the benefiting role of SR in the inflammation-induced angiogenesis in vitro.

A flavonoids compound inhibits osteoclast differentiation by attenuating RANKL induced NFATc-1/c-Fos induction

Function studies of pectolinarigenin demonstrated that, as a natural product, it possesses the regulatory effects on transcription factors (TFs) such as: signal transducer and activator of transcription 3 (STAT3). Herein, we aimed to identify the regulatroy effects of pectolinarigenin on the osteoclastogenesis TFs such as: NFATc1 and c-Fos, and further identify the relevant up-stream signals activity. We initially found pectolinarigenin inhibited receptor activator of nuclear factor-kappa B ligand (RANKL) induced osteoclast formation during the bone marrow-derived macrophages (BMMs) cultures, suggesting that this natural product could act on osteoclast precursors by inhibiting the down signaling cascades of RANKL signaling. Moreover, mechanistical investigation showed pectolinarigenin inhibits RANKL-mediated osteoclastogenesis by attenuating the nuclear factor of activated T cells cytoplasmic 1 (NFATc-1) and c-Fos following the Akt and mitogen activated protein kinases (MAPKs) signaling costimulatory. These findings identify that pectolinarigenin may act as an anti-resorption agent by blocking osteoclast activation.

Investigation of the synergistic effects of haloperidol combined with Calculus Bovis Sativus in treating MK-801-induced schizophrenia in rats

Clinical studies that focused on treating schizophrenia showed that Calculus Bovis Sativus (CBS), a substitute of Calculus Bovis, when used in combination with haloperidol could significantly lower the dosage of haloperidol compared with treatment with haloperidol alone, whereas efficacy was maintained. The aim of this study was to investigate the synergetic anti-schizophrenia effects in rats using CBS in combination with haloperidol. An open field test was conducted to verify the pharmacodynamic effects of a combination treatment of CBS and haloperidol on MK-801-induced schizophrenic rats. Rat plasma concentrations of intragastric haloperidol and intravenous haloperidol were determined after oral administration of a single dose or 1-week of pretreatment with CBS (50 mg/kg). The pharmacodynamic data showed a significant decrease in locomotor activity and an increase in the percentage of the central distance when haloperidol was concomitantly administered with CBS compared with haloperidol administration alone. The AUC0-∞ and Cmax of haloperidol in the orally coadministered groups were significantly higher compared with the oral treatment with haloperidol alone. In conclusion, oral coadministration of CBS with haloperidol resulted in a synergistic effect in rats. The enhanced oral bioavailability of haloperidol when combined with CBS might be attributed to the interaction between them.

Herb-Drug Interactions of Commonly Used Chinese Medicinal Herbs

With more and more popular use of traditional herbal medicines, in particular Chinese herbal medicines, herb-drug interactions have become a more and more important safety issue in the clinical applications of the conventional drugs. Researches in this area are increasing very rapidly. Herb-drug interactions are complicated due to the fact that multiple chemical components are involved, and these compounds may possess diverse pharmacological activities. Interactions can be in both pharmacokinetics and pharmacodynamics. Abundant studies focused on pharmacokinetic interactions of herbs and drugs. Herbs may affect the behavior of the concomitantly used drugs by changing their absorption, distribution, metabolism, and excretion. Studies on pharmacodynamics interactions of herbs and drugs are still very limited. Herb-drug interactions are potentially causing changes in drug levels and drug activities and leading to either therapeutic failure or toxicities. Sometime it can be fatal. The exposures to drugs, lacking of knowledge in the potential adverse herb-drug interactions, will put big risk to patients' safety in medical services. On the contrary, some interactions may be therapeutically beneficial. It may be used to help develop new therapeutic strategies in the future. This chapter is trying to review the development in the area of herb-drug interactions based on the recently published research findings. Information on the potential interactions among the commonly used Chinese medicinal herbs and conventional drugs is summarized in this chapter.

Identification of NF-κB as Determinant of Posttraumatic Stress Disorder and Its Inhibition by the Chinese Herbal Remedy Free and Easy Wanderer

Posttraumatic stress disorder (PTSD) is a mental disorder developing after exposure to traumatic events. Although psychotherapy reveals some therapeutic effectiveness, clinically sustainable cure is still uncertain. Some Chinese herbal formulae are reported to work well clinically against mental diseases in Asian countries, but the safety and their mode of action are still unclear. In this study, we investigated the mechanisms of Chinese remedy free and easy wanderer (FAEW) on PTSD. We used a reverse pharmacology approach combining clinical data to search for mechanisms of PTSD with subsequent in vitro verification and bioinformatics techniques as follows: (1) by analyzing microarray-based transcriptome-wide mRNA expression profiling of PTSD patients; (2) by investigating the effect of FAEW and the antidepressant control drug fluoxetine on the transcription factor NF-κB using reporter cell assays and western blotting; (3) by performing molecular docking and literature data mining based on phytochemical constituents of FAEW. The results suggest an involvement of inflammatory processes mediated through NF-κB in the progression of PTSD. FAEW was non-cytotoxic in vitro and inhibited NF-κB activity and p65 protein expression. FAEW's anti-inflammatory compounds, i.e., paeoniflorin, isoliquiritin, isoliquiritin apioside and ononin were evaluated for binding to IκK and p65-RelA in a molecular docking approach. Paeoniflorin, albiflorin, baicalin, isoliquiritin and liquiritin have been reported to relieve depression in vivo or in clinical trials, which might be the active ingredients for FAEW against PTSD.

Pharmacokinetic interactions of herbal medicines for the treatment of chronic hepatitis

Chronic liver disease is a serious global health problem, and an increasing number of patients are seeking alternative medicines or complementary treatment. Herbal medicines account for 16.8% of patients with chronic liver disease who use complementary and alternative therapies. A survey of the National Health Insurance Research Database in Taiwan reported that Long-Dan-Xie-Gan-Tang, Jia-Wei-Xia-Yao-San, and Xiao-Chai-Hu-Tang (Sho-saiko-to) were the most frequent formula prescriptions for chronic hepatitis used by traditional Chinese medicine physicians. Bioanalytical methods of herbal medicines for the treatment of chronic hepatitis were developed to investigate pharmacokinetics properties, but multicomponent herbal formulas have been seldom discussed. The pharmacokinetics of herbal formulas is closely related to efficacy, efficiency, and patient safety of traditional herbal medicines. Potential herbal formula–drug interactions are another essential issue during herbal formula administration in chronic hepatitis patients. In a survey with the PubMed database, this review article evaluates the existing evidence-based data associated with the documented pharmacokinetics profiles and potential herbal–drug interactions of herbal formulas for the treatment of chronic hepatitis. In addition, the existing pharmacokinetic profiles were further linked with clinical practice to provide insight for the safety and specific use of traditional herbal medicines.

The effects of baicalein on gastric mucosal ulcerations in mice: Protective pathways and anti-secretory mechanisms

Many flavonoids have been shown to present good results for the treatment of gastric ulcers. Baicalein, a bioactive flavonoid derived from the Scutellaria baicalensis Georgi root, possesses several biological effects, such as anti-inflammatory and antioxidant. This study was conducted to assess the gastroprotective properties of baicalein. Anti-ulcerogenic assay was performed using the protocol of ulcer induced by ethanol/HCl in mice; then, the role of presynaptic α₂-receptors, sulfhydryl (SH) compounds, nitric oxide (NO), prostaglandin (PG) and ATP-sensitive K⁺ (K_ATP) channels in gastroprotection of baicalein was investigated. The levels of reduced glutathione (GSH) and the myeloperoxidase (MPO) activity were measured in the gastric mucosa. Parameters of gastric secretion (volume, [H⁺] and pH) were determined with or without the presence of the secretagogue agent histamine, as well as mucus in gastric contents, by the pylorus ligation model. In vitro H⁺,K⁺-ATPase activity was also determined. Baicalein (10, 30 and 100 mg/kg) exhibited a dose related gastroprotective effect (P < 0.001) against acidified ethanol-induced lesions. The intraperitoneal treatment of mice with a α₂-adrenoreceptor antagonist (yohimbine; 2 mg/kg), a SH compounds blocker (N-ethylmaleimide, NEM; 10 mg/kg), a non-selective inhibitor of NO synthase (N_w-nitro-L-arginine methyl ester hydrochloride, L-NAME; 10 mg/kg), a non-selective inhibitor of cyclo-oxygenase (indomethacin; 10 mg/kg) or a K_ATP channel blocker (glibenclamide; 10 mg/kg) was able to reverse (P < 0.001) the gastroprotective response caused by baicalein (30 mg/kg). Baicalein (30 mg/kg; P < 0.05) was able to increase GSH levels and decreasing MPO activity. The intraduodenal treatment with baicalein (30 and 100 mg/kg) significantly increased (P < 0.05) the gastric mucus secretion. Additionally, the treatment with baicalein reduced (30 and 100 mg/kg; P < 0.05) the secretion volume and total acid secretion, and also increased (10, 30 and 100 mg/kg; P < 0.001) the pH value, after pylorus ligature. Baicalein (30 mg/kg) was also effective in inhibiting the effects of histamine on gastric secretion (volume, [H⁺] and pH; P < 0.001). Baicalein at 10 and 30 μg/mL showed anti-H⁺,K⁺-ATPase activity. In conclusion, the present results provide convincing evidence that baicalein could be used as a cytoprotective (preventive effect) and anti-ulcerogenic (anti-secretory effect) agent in the gastric ulcers.

Oroxyloside prevents dextran sulfate sodium-induced experimental colitis in mice by inhibiting NF-κB pathway through PPARγ activation

Oroxyloside, as a metabolite of oroxylin A, may harbor various beneficial bioactivities which have rarely been reported in the previous studies. Here we established the dextran sulfate sodium (DSS)-induced experimental colitis and evaluated the anti-inflammatory effect of oroxyloside in vivo. As a result, oroxyloside attenuated DSS-induced body weight loss, colon length shortening and colonic pathological damage. Furthermore, oroxyloside inhibited inflammatory cell infiltration and decreased myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) activities as well. The production of pro-inflammatory cytokines in serum and colon was also significantly reduced by oroxyloside. We unraveled the underlying mechanisms that oroxyloside inhibited NF-κB pathway by activating Peroxisome Proliferator-Activated Receptor γ (PPARγ) to attenuate DSS-induced colitis. Moreover, we investigated the anti-inflammatory effect and mechanisms of oroxyloside in the mouse macrophage cell line RAW264.7 and bone marrow derived macrophages (BMDM). Oroxyloside decreased several LPS-induced inflammatory cytokines, including IL-1β, IL-6 and TNF-α in RAW264.7 and BMDM. We also found that oroxyloside inhibited LPS-induced activation of NF-κB signaling pathway via activating PPARγ in RAW 264.7 and BMDM. Docking study showed that oroxyloside could bind with PPARγ. GW9662, the inhibitor of PPARγ, and PPARγ siRNA transfection blocked the effect of oroxyloside on PPARγ activation. Our study suggested that oroxyloside prevented DSS-induced colitis by inhibiting NF-κB pathway through PPARγ activation. Therefore, oroxyloside may be a promising and effective agent for inflammatory bowel disease (IBD).

ADMINISTRATION OF H2 BLOCKERS IN NSAID INDUCED GASTROPATHY IN RATS: effect on histopathological changes in gastric, hepatic and renal tissues

ABSTRACT Background Nonsteroidal anti-inflammatory drugs induces gastric mucosal lesions because of its acidic properties. Ranitidine, an H2 receptor antagonist, has proved beneficial in patients with gastric ulcers. Objective The present study was performed to assess the effect of administering ranitidine in Nonsteroidal anti-inflammatory drugs (diclofenac, nimesulide) induced gastropathy, and their effect on the histopathology of stomach, kidney and liver. Methods Diclofenac, nimesulide, and ranitidine were administered in doses of 2, 4, and 6 mg/kg, p.o. once daily for 14 days, and their effect on gastric volume, acidity, mean ulcer number, and gastric pH. In addition, histopathological examination was also performed on sections of stomach, kidney and liver. Results Following the administration of diclofenac or nimesulide, all the gastric parameters were significantly altered as well as the histopathology of stomach, liver and kidney. In the control group, the renal sections showed normal glomeruli with no thickening of glomerular basement membrane, while in diclofenac alone, nimesulide alone, and ranitidine with nimesulide groups, the thickening of glomerular basement membrane was observed. These alterations were observed to be reversed in the ranitidine with diclofenac group. In the sections from the liver, the control group showed anastomosing plates and cords of cuboidal hepatocytes with round well stained nuclei and abundant cytoplasm. In the ranitidine with diclofenac, and ranitidine with nimesulide groups, mild dilatation of sinusoids is seen coupled with prominence of central vein. In the diclofenac alone and nimesulide alone groups, the proximal and distal convoluted tubules show mild focal tubular necrosis. In the gastric sections, the control group showed several folds forming villi, and the epithelial lining surface of the mucosa. In the ranitidine with diclofenac, and ranitidine with nimesulide groups, the duodenum showed scattered inflammatory cells composed predominantly of lymphocytes. In diclofenac alone and nimesulide alone group, the sections from the gastric areas showed partial necrosis and mild chronic inflammation respectively. Conclusion The study, therefore, has provided therapeutic rationale towards simultaneous administration of H2 receptor blocker ranitidine with diclofenac to be more beneficial as compared to ranitidine with nimesulide, to minimise the gastric intolerance of diclofenac in long term treatment of inflammatory conditions.