Protective Effects of Chlorogenic Acid against Experimental Reflux Esophagitis in Rats

Xuanfu Daizhe Tang alleviates reflux esophagitis in rats by inhibiting the STAT1/TREM-1 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Reflux esophagitis (RE) is a common chronic inflammatory disease of the esophageal mucosa with a high prevalence and recurrence rate, for which a satisfactory therapeutic strategy is still lacking. Chinese medicine has its characteristics and advantages in treating RE, and the clinical application of Xuanfu Daizhe Tang (XDT) in treating RE has achieved sound therapeutic effects. However, there needs to be more research on its mechanism of action.

AIM OF THE STUDY

The present work aimed to investigate the mechanism of XDT action in RE through the Signal Transducer and Activator of Transcription 1 (STAT1)/Triggering Receptor Expressed on Myeloid cells-1 (TREM-1) pathway.

MATERIALS AND METHODS

The main active components of XDT were analyzed by ultra-performance liquid chromatography-mass spectrometer (UPLC-MS). The effect of XDT on RE was evaluated in a rat model of RE induced by "Cardioplasty + pyloric ligation + Roux-en-Y esophagojejunostomy". Each administration group was treated by gavage. The degree of damage to the esophageal mucosa was evaluated by visual observation, and the Potential of Hydrogen (PH) method and Hematoxylin-eosin staining (HE) staining were performed. Serum levels of Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Tumor Necrosis Factor alpha (TNF-α), and Inducible Nitric Oxide Synthase (iNOS) were measured by ELISA. Quantitative Real-time PCR (qPCR), Western Blot (WB), and Immunofluorescence (IF) methods were used to detect Claudin-4, Claudin-5, TREM-1, and p-STAT1 in esophageal tissues for studying the mechanism of action and signaling pathway of XDT. Immunohistochemistry (IHC) analysis was used to detect the expression of TREM-1 and CD68 in esophageal tissues. Flow Cytometry (FC) was used to detect the polarization of macrophages in the blood. After conducting preliminary experiments to verify our hypothesis, we performed molecular docking between the active component of XDT and STAT1 derived from rats and parallel experiments with STAT1 inhibitor. The selective increaser of STAT1 transcription (2-NP) group was used to validate the mechanism by which XDT acts.

RESULTS

XDT alleviated esophageal injury and attenuated histopathological changes in RE rats. XDT also inhibited the inflammatory response and decreased serum IL-1β, IL-6, TNF-α, and iNOS levels in RE rats. qPCR and WB results revealed that XDT inhibited the expression of Claudin-4, Claudin-5, TREM-1, and STAT1 in the esophageal mucosa of RE rats. IHC and FC results showed that XDT reduced TREM-1 levels in esophageal tissues and polarized macrophages toward M2. The molecular docking results showed that rat-derived STAT1 can strongly bind to Isochronogenic acid A in XDT. The parallel experimental results of STAT1 inhibitor showed that XDT has anti-inflammatory effects similar to STAT1 inhibitors. The 2-NP group confirmed that XDT exerts its therapeutic effect on reflux esophagitis through the STAT1/TREM-1 pathway, with STAT1 as the upstream protein.

CONCLUSIONS

This study suggests that XDT may treat reflux esophagitis by modulating the STAT1/TREM-1 pathway.

Atractylenolide III ameliorated reflux esophagitis via PI3K/AKT/NF-κB/iNOS pathway in rats

Reflux esophagitis (RE), an esophageal inflammation caused by reflux of gastric contents, often damages the lower esophagus, seriously affecting the quality of life of patients. This study aims to investigate the therapeutic effects and underlying molecular mechanisms of atractylenolide III (ATL III) on RE model rats. In this research, the RE rat model is established sequentially following hemipyloric ligation, cardia transection, and hydrochloric acid perfusion. Further, the RE-induced rats are intragastrically administrated with ATL III (0.6, 1.2, and 2.4 mg/kg/D) for 28 days to evaluate ATL III therapeutic effects. To study the molecular mechanism, RE rats are treated with a phosphoinositide-3 kinase (PI3K) agonist (740 Y-P) combined with ATL III. The histopathological changes in the esophagus are eventually observed by hematoxylin & eosin (H&E) staining. In addition to changes in gastric pH and levels of reactive oxygen species (ROS), enzyme-linked immunosorbent assay (ELISA) and Western blot analyses are used to detect the expression levels of tumor necrosis factor-α (TNF-α, mmol/L), interleukin (IL)-8, IL-6, IL-1β in the esophageal tissues. As a result, the lesions in the esophageal tissues of RE rats are alleviated, decreasing the macroscopic observation scores of the esophageal mucosa after ATL III treatment,. The experimental results indicated significantly increased pH value of the gastric contents and reduced ROS, thiobarbituric acid reactants (TBARS), TNF-α, IL-8, IL-6, and IL-1β levels, as well as expression levels of p-PI3K, p-AKT, iNOS, and nuclear NF-κB proteins in esophageal tissues. In conclusion, the study indicated that ATL III could efficiently treat RE in rats by inhibiting oxidative stress and inflammatory damage through the PI3K/AKT/NF-κB/iNOS pathway.

Two Species Origins Comparison of Herba Patriniae based on Their Ingredients Profile by UPLC-QTOF/MS/MS and Orthogonal Partial Least Squares Discriminant Analysis

Herba Patriniae (HP) is widely used as a medicinal and edible material in China. Besides food value, HP attracts more attention due to its medicinal potential. Patrinia villosa Juss. ( PV ) and Patrinia scabiosaefolia Fisch. ( PS ) are the two species origins of HP. These two of HP show different effects on cell proliferation, migration, angiogenesis and anti-diabetic. As we have previously reported, PV and PS show significant differences on their anti-inflammatory ability in the same experimental model. Comparing the ingredient profiles of two different sources will not only facilitate the understanding of their medicinal effects, but also help the development and research of new activities. However, still now, there is no systematic and detailed study to compare the components of PV and PS . In present study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was employed to achieve a high-throughput qualitative and thorough analysis of the chemical composition spectrum of HP. A total of 164 compounds were identified, among these compounds, 127 compounds were identified from PV , and 107 compounds were identified from PS . Most of the chemical components was discovered for the first time. Flavonoids, saponins, terpenoids and organic acids, as the main ingredients in PV and PS were 45.45%vs 28.46%, 12.61% vs 32.09%, 14.33% vs 22.38% and 14.58% vs 6.79%, respectively. Flavonoids are the main components of PV , while PS is rich in saponins. PV and PS were classified into two groups by principal component analysis (PCA) and screened out the main molecular differences responsible by orthogonal partial least squares discriminant analysis (OPLS-DA). All the results will be a guide for the quality control, functional activity research, or better clinic use based on the ingredients profile between these two species. Besides, this first study on ingredients profile of two species origins will be beneficial for potential and best resources utilization of both PV and PS .

Lifestyle, WCRF/AICR Recommendations, and Esophageal Adenocarcinoma Risk: A Systematic Review of the Literature

One of the most notable changes in the epidemiology of esophageal cancer (EC) is the rising incidence and prevalence of esophageal adenocarcinoma (EAC) in developed countries. The aim of this systematic review was to collect and summarize all the available evidence regarding lifestyle, diet, and EAC risk. We searched the PubMed and Scopus databases in January 2021 for studies providing information about lifestyle, diet, WCRF/AICR recommendations, and EAC risk; published in English; without a time filter. The Newcastle-Ottawa Scale was used to assess risk of bias. The results are stratified by risk factor. A total of 106 publications were included. Half of the case-control studies were judged as high quality, whilst practically all cohort studies were judged as high quality. Body mass index and waist circumference were associated with increased EAC risk. Physical activity did not appear to have a significant direct role in EAC risk. A diet rich in fruit, vegetables, and whole grains appeared to be more protective than a Western diet. Alcohol does not seem to be related to EAC, whereas smokers, particularly heavy smokers, have an increased risk of EAC. Prevention remains the best option to avert EAC. Comprehensible and easy to follow recommendations should be provided to all subjects. Protocol ID number: CRD-42021228762, no funds received.

Mechanistic insights into the protective effects of chlorogenic acid against indomethacin-induced gastric ulcer in rats: Modulation of the cross talk between autophagy and apoptosis signaling

BACKGROUND

This study aimed to investigate the gastroprotective effect of chlorogenic acid (CGA) against Indomethacin (IND)-induced gastric ulcer (GU) in rats and its underlying mechanism, especially through autophagic and apoptotic pathways.

METHODS

Seventy-five rats were divided into five groups; control, IND (50 mg/kg, p.o.), CGA (100 mg/kg, p.o., 14 days), IND pretreated with CGA (50 mg/kg or 100 mg/kg, p.o., 14 days). The stomach tissues were examined to calculate the ulcer index and analyze markers of autophagy (beclin-1, LC3-II/LC3-I and p62), lysosomal function (cathepsin-D) and apoptosis (Bcl-2, Bax and caspase-3), along with expression of Akt/mTOR pathway using western blot or ELISA techniques. In addition, viability of gastric mucosal cells was detected by flowcytometry. Structural changes were assessed histologically, while autophagic and apoptotic changes of gastric mucosa were observed by transmission electron microscopy.

RESULTS

CGA exhibited a dose-dependent gastroprotective effect by reversing IND-induced accumulation of autophagic vacuoles, significant reduction in beclin-1, LC3-II/LC3-I, and p62 levels, and down-regulation of p-Akt/p-mTOR expression. CGA100 also restored normal autolysosomal function by modulation of cathepsin-D levels. Furthermore, pretreatment with CGA100 was significantly associated with an increase in antiapoptotic protein Bcl-2 along with a decrease in proapoptotic Bax and caspase-3 proteins in such a way that impairs IND-induced apoptosis. This was confirmed by CGA-induced significant decrease in annexin V⁺ cells.

CONCLUSIONS

The natural compound CGA offers a novel gastroprotective intervention against IND-induced GU through restoration of normal autophagic flux, impairment of apoptosis in a crosstalk mechanism mediated by Akt/mTOR pathway reactivation, and alleviation of IND-induced lysosomal dysfunction.

Protective Effects of Inflammation of Curcumae Longae Rhizoma 30% EtOH Extract on Acute Reflux Esophagitis Rats

Gastroesophageal reflux disease (GERD) is induced by the reflux of stomach contents or gastric acid, pepsin into the esophagus for prolonged periods of time due to defection of the lower esophageal sphincter. Reflux esophagitis is a disease found in less than 50% of GERD patients. This study is aimed at evaluating the protective effect of Curcumae longae Rhizoma 30% EtOH extract (CLR) in acute reflux esophagitis (ARE) rats. CLR measured antioxidant activity through in vitro experiments. Based on the results, we performed experiments in vivo. Before 90 min ARE induction, CLR was administered orally by concentration. ARE was derived by linking the metastatic junction between pylorus and forestomach and corpus in Sprague-Dawley rats. And rats were sacrificed 5 h after surgery. We analyzed the expression of antioxidant and inflammatory-related markers by western blot and observed the production of alanine aminotransferase (ALT), aspartate aminotransferase (AST), reactive oxygen species (ROS), peroxynitrite (ONOO⁻), and thiobarbituric acid reactive substance (TBARS). The administration of CLR reduced esophagus tissue damage in rats with acute reflux esophagitis and decreased the elevated ALT, AST, ROS, ONOO⁻, and TBARS. In addition, CLR effectively increased antioxidant-related factors and reduced inflammatory protein. Overall, these results suggest that CLR would be used as a therapeutic material in protection and treatment for ARE. Overall, CLR treatment informed that markedly ameliorated inactivation of NF-κB led to the inhibition of the expressions of proinflammatory proteins. These results suggest that CLR would be used as a therapeutic material in protection and treatment for ARE.

The Impact of Whole Grain Intake on Gastrointestinal Tumors: A Focus on Colorectal, Gastric, and Esophageal Cancers

Cereals are one of staple foods in human diet, mainly consumed as refined grains. Nonetheless, epidemiological data indicate that whole grain (WG) intake is inversely related to risk of type 2 diabetes, cardiovascular disease, and several cancer types, as well as to all-cause mortality. Particularly responsive to WG positive action is the gastrointestinal tract, daily exposed to bioactive food components. Herein, we shall provide an up-to-date overview on relationship between WG intake and prevention of gastrointestinal tumors, with a particular focus on colorectal, stomach, and esophagus cancers. Unlike refined counterparts, WG consumption is inversely associated with risk of these gastrointestinal cancers, most consistently with the risk of colorectal tumor. Some WG effects may be mediated by beneficial constituents (such as fiber and polyphenols) that are reduced/lost during milling process. Beside health-promoting action, WGs are still under-consumed in most countries; therefore, World Health Organization and other public/private stakeholders should cooperate to implement WG consumption in the whole population, in order to reach nutritionally effective intakes.

The Efficacy and Safety of GCWB104 (<i>Flos</i> Lonicera Extract) in Functional Dyspepsia: A Single-Center, Randomized, Double-Blind, Placebo-Controlled Study

<b>Background/Aims:</b> The <i>Flos Lonicera</i> extract GCWB104 has been shown to have significant protective effects against gastritis and gastric ulcers <i>in vivo</i>. The aim of this study was to investigate the efficacy and safety of GCWB104 in subjects with functional dyspepsia (FD). <b>Methods:</b> In this single-center, double-blind, randomized clinical trial, 92 subjects diagnosed with FD using the Rome III criteria were allocated to either the test group (300 mg of GCWB104, containing 125 mg of <i>Flos Lonicera</i> extract, twice daily) or the placebo group (300 mg placebo, twice daily). The total score improvement on the Gastrointestinal Symptom Rating Scale (GSRS) for individual symptoms, changes in antioxidant levels, changes in dyspepsia-related quality of life according to the Nepean Dyspepsia Index (NDI), and adverse effects were compared before and after 8 weeks of treatment. <b>Results:</b> The differences in total GSRS scores and score improvements after 8 weeks of treatment were significant between the GCWB104 and control groups (p=0.0452 and p=0.0486, respectively). Thirteen of 15 individual symptoms on the GSRS improved in the GCWB104 group, while six symptoms improved in the control group. In addition, statistically significant changes in rumbling, loose stool, and stool urgency were observed in the GCWB104 group. Blood 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, known as antioxidants, showed significant reductions after 8 weeks of administration of GCWB104. There were no adverse events related to treatment with GCWB104. <b>Conclusions:</b> GCWB104 safely contributed to improvements in mild to moderate FD and irritable bowel syndrome symptoms. Antioxidant effects of GCWB104 were also suggested (Clinicaltrials.gov number NCT04008901).

Nephroprotective effects of chlorogenic acid against sodium arsenite-induced oxidative stress, inflammation, and apoptosis

BACKGROUND

Chronic exposure to arsenic (As) leads to serious renal disorders. Chlorogenic acid (CGA), a phenolic compound, has several well known physiological benefits, including antioxidant and anti-inflammatory activities. The present study investigated the potential renoprotective effects of CGA on sodium arsenite (NaAsO₂ )-induced kidney damage in mice. The mice were randomly allocated into five groups to receive daily treatment with CGA (200 mg kg^-1 ), NaAsO₂ (5 mg kg^-1 ), NaAsO₂ + CGA (100 mg kg^-1 ), NaAsO₂ + CGA (200 mg kg^-1 ), or a control for 28 days.

RESULTS

In the NaAsO₂ -treated group, NaAsO₂ induced significant renal dysfunction, oxidative damage, inflammation, and apoptosis, as demonstrated by marked increases in urea and creatinine levels accompanied by a decrease in the kidney index. Considerable increases in malondialdehyde and nitric oxide levels and parallel decreases in various antioxidant markers (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione) levels were also detected in the renal tissues of NaAsO₂ -treated mice. NaAsO₂ exposure was associated with marked increases in renal inflammatory markers (interleukin-1β and tumor necrosis factor-α) and apoptosis indicators including Bax and caspase-3 levels contaminant, with a marked decrease in Bcl-2, an anti-apoptotic protein, in the NaAsO₂ -treated group compared with the control group. However, pretreatment with CGA substantially mitigated the renal injury and dysfunction associated with NaAsO₂ exposure by reducing tissue inflammation and apoptosis and improving the antioxidant status. The CGA pretreatment also alleviated the NaAsO₂ -induced histological alterations in renal tissues.

CONCLUSION

Taken together, our results suggest the efficacy of CGA in alleviating As-mediated renal tissue damage. © 2020 Society of Chemical Industry.

Ameliorative effects of Magnolia sieboldii buds hexane extract on experimental reflux esophagitis

Gastroesophageal reflux disease (GERD) is a disease that stomach contents continually refluxing into esophagus causes symptoms and/or complications. The study was working to find natural plant extracts with good effects and small side effects to treat reflux esophagitis (RE). The anti-inflammatory effects of hexane extract of Magnolia sieboldii (MsHE) were conducted on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The ameliorative effects of MsHE on esophageal damage in rats induced by gastric acid reflux was explored in vivo. The results showed that MsHE decreased the production of nitric oxide (NO) and expression levels of iNOS, COX-2 and TNF-α on LPS-stimulated RAW 264.7 cells and MsHE treatment ameliorated the rats' esophageal tissue damage induced by gastric acid and inhibited the increase of inflammatory mediators and pro-inflammatory cytokines by regulating NF-κB signaling pathway. In addition, MsHE protected the function of barrier of epithelial cells against inflammatory conditions through increasing the expression of tight junctions. Furthermore, liquid chromatography-mass spectrometry analysis was used for determine the active ingredients contained in MsHE. The results show that MsHE can alleviate experimental rat RE by regulating NF-κB signaling pathway. In summary, MsHE may be used as a source material of drug candidate for the treatment of RE.

Tojapride Reverses Esophageal Epithelial Inflammatory Responses on Reflux Esophagitis Model Rats

OBJECTIVE

To investigate the mechanism of Tojapride, a Chinese herbal formula extract, on strengthening the barrier function of esophageal epithelium in rats with reflux esophagitis (RE).

METHODS

Ten out of 85 SD rats were randomly selected as the sham group (n10), and 75 rats were developed a reflux esophagitis model (RE) by the esophageal and duodenal side-to-side anastomosis. Fifty successful modeling rats were divided into different medicated groups through a random number table including the model, low-, medium-, and high-dose of Tojapride as well as omeprazole groups (n10). Three doses of Tojapride [5.73, 11.46, 22.92 g/(kg•d)] and omeprazole [4.17 mg/(kg•d)] were administrated intragastrically twice daily for 3 weeks. And the rats in the sham and model groups were administered 10 mL/kg distilled water. Gastric fluid was collected and the supernatant was kept to measure for volume, pH value and acidity. Esophageal tissues were isolated to monitor the morphological changes through hematoxylin-eosin (HE) staining, and esophageal epithelial ultrastructure was observed by transmission electron microscopy. The expressions of nuclear factor kappa-light-chain-enhancer of activated B cells p65 (NF-KBp65), κB kinase beta (IKKß), occludin, and zonula occludens-1 (ZO-1) in the esophageal tissues were measured by immunohistochemistry and Western blot, respectively.

RESULTS

The gastric pH value in the model group was significantly lower than the sham group (P<0.05). Compared with the model group, gastric pH value in the omeprazole and medium-dose of Tojapride groups were significantly higher (P<0.05). A large area of ulceration was found on the esophageal mucosa from the model rats, while varying degrees of congestion and partially visible erosion was observed in the remaining groups. Remarkable increase in cell gap width and decrease in desmosome count was seen in RE rats and the effect was reversed by Tojapride treatment. Compared with the sham group, the IKKß levels were significantly higher in the model group (P<0.05). However, the IKKß levels were down-regulated after treatment by all doses of Tojapride (P<0.01 or P<0.05). The occluding and ZO-1 levels decreased in the model group compared with the sham group (Ps0.01 or Ps0.05), while both indices were significantly up-regulated in the Tojapride-treated groups (P<0.01 or P<0.05).

CONCLUSIONS

Tojapride could improve the pathological conditions of esophageal epithelium in RE rats. The underlying mechanisms may involve in down-regulating the IKKß expression and elevating ZO-1 and occludin expression, thereby alleviating the inflammation of the esophagus and strengthening the barrier function of the esophageal epithelium.

Inhibitory Effects of Urtica thunbergiana Ethanol Extract on Atopic Dermatitis-Induced NC/Nga Mice

Atopic dermatitis (AD) is a chronic, inflammatory skin disease that persists or repeatedly recurs in both childhood and adulthood. Urtica thunbergiana (UT) is an aroma herb with little-known pharmacological effects and anti-inflammatory activities against AD. This study investigated the immunomodulatory efficacy of 50% ethanol-extracted UT in necrosis factor-alpha/interferon-gamma (TNF-α/IFN-γ)-stimulated HaCaT cells in vitro and AD-Biostir-induced NC/Nga mice in vivo. The results showed that UT exhibits a dose-dependent increase in scavenged free radicals, reaching 76.0% ± 1.4% of scavenged 1,1-diphenyl-2-picrylhydrazyl at a concentration of 250 µg/mL. In addition, UT significantly downregulated the mRNA expression of the following pro-inflammatory cytokines and chemokines in TNF-α/IFN-γ-stimulated HaCaT cells: interleukin (IL)-6, IL-8, thymus- and activation-regulated chemokine, macrophage-derived chemokine, and regulated on activation normal T expressed and secreted. UT-treated HaCaT cells showed inhibition of the overexpression of chemokine-regulated signaling molecules, such as nuclear factor-kappa B, inhibitor of kappa B (IκBα), signal transducer and activator of transcription 1, and mitogen-activated protein kinases (MAPKs). UT dietary administration in AD-Biostir-induced NC/Nga mice treated and improved AD-like symptoms, such as scales, epidermal thickening, the dermatitis severity score, high trans-epidermal water loss, reduced skin hydration, increased mast cells, elevated serum immunoglobulin E levels, and an enlarged spleen. UT treatment inhibited the expression of phosphorylated forms of MAPKs, nuclear factor of activated T-cells 1, and regulator IκBα. It also upregulated filaggrin (FLG) production. Therefore, UT shows high anti-AD activity both in vitro and in vivo, and can be a useful anti-AD agent.

Dichloromethane Extracts of Geranium Koreanum Kom. Alleviates Esophagus Damage in Acute Reflux Esophagitis-Induced Rats by Anti-Inflammatory Activities

Reflux esophagitis (RE) is a gastrointestinal disease caused by the reflux of gastric acid and stomach contents, and it leads to esophageal damage. Therefore, it is necessary to study the improvement of esophageal damage on a RE-induced model. The present study was accomplished to demonstrate the protective effects of a dichloromethane fraction of Geranium koreanum (DGK) plant on esophageal damage in an acute RE rat model. First, we examined the potential of anti-inflammatory effects of various fractions measured by cell cytotoxicity, morphological changes and nitric oxide (NO) production on lipopolysaccharide (LPS)-induced Raw 264.7 macrophage cells. Then, to evaluate the protective effects on RE, rats were partitioned into the following groups: normal control, RE-induced control and RE rats pre-treated with DGK 100 and 200 mg/kg body weight. The esophageal mucosal ulcer ratio was measured by the Image J program and histological changes were examined using a hematoxylin and eosin staining of the esophageal mucosa. The expression of pro-inflammatory proteins, cytokines and tight junction proteins involved in the esophageal mucosal damage were investigated using Western blotting and an enzyme-linked immunosorbent assay (ELISA) kit with esophagus tissue. DGK chemical profile and phenolic contents were analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). The results showed that DGK exhibited anti-inflammatory effects against LPS-stimulated cells by significantly inhibiting NO production. Additionally, the results in vivo showed that improvement effects of DGK on esophageal mucosal damage. The expression of inflammatory proteins involved in nuclear factor κB (NF-κB) signaling pathways and tight junction protein (claudin-4 and -5) were significantly decreased in esophageal mucosa. We found the potential of DGK as source of replacement therapy products for inflammatory and RE disease.

Low-Molecular-Weight Oligonol, a Polyphenol Derived from Lychee Fruit, Attenuates Experimental Reflux Esophagitis and HCl/Ethanol-Induced Gastric Ulcer

Oligonol, a polyphenol derived from lychee fruit, is produced by an oligomerization process that converts high-molecular-weight polyphenol polymers into low-molecular-weight oligomers. Evidence suggests that oligonol exerts its beneficial effects based on antioxidant and anti-inflammatory properties. This study was the first to investigate the antioxidative and anti-inflammatory effects of oligonol on gastroesophageal inflammatory models: surgically induced acute reflux esophagitis (RE) and gastric ulcer (GU) induced by HCl/ethanol. In the in vitro study, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) radical scavenging assays were performed to determine the antioxidant activity of oligonol. The experimental groups were each composed of normal, vehicle, and oligonol groups. RE rats and GU mice were treated orally with oligonol (100 mg/kg bw) or distilled water as a vehicle (n = 8 for each group). Oligonol exhibited potent free radical-scavenging capacities for DPPH and ABTS radicals, activities that were similar to those of ascorbic acid. The in vivo study revealed that oligonol consumption significantly prevented RE and GU formation and decreased the gross mucosal injury from oxidative stress. Oligonol decreased the reactive oxygen species levels and elevated levels of both inflammatory mediators and cytokines (p-IκB, NF-κBp65, COX-2, iNOS, TNF-α, and IL-1β) in the RE and GU models. Oligonol had a protective effect against oxidative stress by regulating antioxidant enzyme (superoxide dismutase, catalase, and GPx-1/2) activities in GU mice. Oligonol has potential as a preventive and therapeutic agent for gastroesophageal inflammatory diseases, including RE and GU.

Chlorogenic acid prevents inflammatory responses in IL‑1β‑stimulated human SW‑1353 chondrocytes, a model for osteoarthritis

Chlorogenic acid (CGA), which is a natural compound found in various plants, has been reported to exert notable anti‑inflammatory activities. The present study investigated the effects and underlying mechanism of CGA on interleukin (IL)‑1β‑induced osteoarthritis (OA) chondrocytes. An in vitro OA‑like chondrocyte model was established using IL‑1β‑stimulated human SW‑1353 chondrocytes. Cell viability was assessed using an MTT assay. Nitric oxide (NO) and IL‑6 production were evaluated by Griess reaction and ELISA, respectively. The expression levels of inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), cyclooxygenase 2 (COX‑2), collagen II, matrix metalloproteinase (MMP)‑13, p65 nuclear factor (NF)‑κB and inhibitor‑κBα were detected by western blot analysis. The results indicated that CGA reversed IL‑1β‑induced increases in iNOS/NO, IL‑6, MMP‑13 and COX‑2/PGE2 production, and reversed the IL‑1β‑mediated downregulation of collagen II. In addition, the data suggested that CGA was capable of inhibiting the IL‑1β‑induced inflammatory response, at least partially via the NF‑κB signaling pathway. In conclusion, CGA may be considered a suitable candidate agent in the treatment of OA.

Chlorogenic acid ameliorates isoproterenol-induced myocardial injury in rats by stabilizing mitochondrial and lysosomal enzymes

This study was deliberated to aspire the effects of chlorogenic acid (CGA) against myocardial infarction (MI) induced by Isoproterenol (ISO), in a rat model. In the pathology of MI, enzymes released due to the mitochondrial and lysosomal lipid peroxidation play an integral role. Induction of rats with ISO (85mg/kg BW) for 2 consecutive days resulted in a significant decrease in the activities of heart mitochondrial enzymes isocitrate dehydrogenase (ICDH), α-ketoglutarate dehydrogenase (α-KGDH), succinate dehydrogenase (SDH) and malate dehydrogenase (MDH). The activities of lysosomal enzymes (β- glucosidase, β-glucuronidase, α-galactosidase, β-galactosidase, cathepsin-B and cathepsin-D) were increased significantly in the heart tissue. A prominent expression of LDH 1 and LDH 2 isoenzymes in the serum were observed and changes in the Electrocardiographic (ECG) patterns were also recorded in the ISO-induced rats. The prior administrations of CGA (40mg/kg BW) for 19days markedly ameliorated ISO induced alterations in ECG and significantly restored the activities of all the above enzymes in the heart of ISO-induced rats, which substantiates the stress stabilizing action of CGA. Oral administration of CGA (40mg/kg BW) to normal rats did not show any significant changes. These biochemical functional alterations were supported by the histology of heart (Massion's trichrome and Picrosirius red staining for collagen formation). Thereupon, this study shows that 40mg/kg BW of CGA gives protection against ISO-induced MI and demonstrates that CGA has a significant effect in the protection of heart.

Antioxidant and Anti-Inflammatory Effects of Rhei Rhizoma and Coptidis Rhizoma Mixture on Reflux Esophagitis in Rats

The purpose of this study was to investigate the antioxidant and anti-inflammatory effects of the combined extract of Rhei rhizoma and Coptidis rhizoma (RC-mix) in experimental model of acute reflux esophagitis. The antioxidant activity was assessed by in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. RC-mix was given at 100, 200, and 400 mg/kg body weight 2 h prior to induction of reflux esophagitis (RE). After 5 h, the effects of RC-mix treated rats were compared with those of normal and control rats. The representative flavonoid contents of RC-mix, such as sennoside A, epiberberine, coptisine, palmatine, and berberine, were detected using HPLC. The elevated esophageal mucosa damage was markedly ameliorated by RC-mix treatment in a dose-dependent manner. Furthermore, the administration of RC-mix reduced the increase of serum reactive oxygen species (ROS) and peroxynitrite (ONOO(-)). The improvement of superoxide dismutase (SOD) and heme oxygenase-1 (HO-1) levels were marked in the group given RC-mix. Moreover, the elevation of inflammatory mediators and cytokines by nuclear factor-kappa B (NF-κB) activation in control rats decreased by RC-mix pretreatment. These results indicate that RC-mix treatment reduces the pathological states of esophagitis via regulating NF-κB mediated inflammation related to oxidative stress.

Protective effect of Rhei Rhizoma on reflux esophagitis in rats via Nrf2-mediated inhibition of NF-κB signaling pathway

Background

Rhei Rhizoma has been widely used as a traditional herbal medicine to treat various inflammatory diseases. The present study was conducted to evaluate its anti-inflammatory activity against experimental reflux-induced esophagitis (RE) in SD rats.

Methods

Rhei Rhizoma was administered at 125 or 250 mg/kg body weight per day for 7 days prior to the induction of reflux esophagitis, and its effect was compared with RE control and normal rats.

Results

Rhei Rhizoma administration markedly ameliorated mucosal damage on histological evaluation. The elevated reactive oxygen species in the esophageal tissue of RE control rats decreased with the administration of Rhei Rhizoma. RE control rats exhibited the down-regulation of antioxidant-related proteins, such as nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression levels, in the presence of esophagitis; however, the levels with Rhei Rhizoma treatment were significantly higher than those in RE control rats. Moreover, RE control rats exhibited the up-regulation of protein expressions related to oxidative stress in the presence of esophagitis, but Rhei Rhizoma administration significantly reduced the expression of inflammatory proteins through mitogen-activated protein kinase (MAPK)-related signaling pathways. The protein expressions of inflammatory mediators and cytokines by nuclear factor-kappa B (NF-κB) activation were modulated through blocking the phosphorylation of inhibitor of nuclear factor kappa B (IκB)α.

Conclusion

Our findings support the therapeutic evidence for Rhei Rhizoma ameliorating the development of esophagitis via regulating inflammation through the activation of the antioxidant pathway.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-015-0974-z) contains supplementary material, which is available to authorized users.

Protective Effect of Flos Lonicerae against Experimental Gastric Ulcers in Rats: Mechanisms of Antioxidant and Anti-Inflammatory Action

Flos Lonicerae is one of the oldest and most commonly prescribed herbs in Eastern traditional medicine to treat various inflammatory diseases. In the present study, we investigated the effects of ethyl acetate fraction of Flos Lonicerae (GC-7101) on experimental gastric ulcer models and its mechanisms of action in gastric ulcer healing. The pharmacological activity of GC-7101 was investigated in rats on HCl/EtOH, indomethacin, water immersion restraint stress induced acute gastric ulcer, and acetic-acid-induced subchronic gastric ulcer. To determine its gastroprotective mechanisms, gastric wall mucus secretion, mucosal PGE₂, mucosal NO content, nuclear translocation of NF-κB, mRNA expression of inflammatory cytokines, lipid peroxidation and glutathione content, and superoxide dismutase and catalase activities were measured. GC-7101 significantly attenuated development of acute gastric ulcer and accelerated the healing of acetic-acid-induced subchronic gastric ulcer. In HCl/EtOH-induced gastric ulcer, GC-7101 markedly enhanced gastric wall mucus content which was accompanied by increased mucosal PGE₂ and NO production. Furthermore, treatment of GC-7101 exhibited anti-inflammatory and antioxidant activities as evidenced by decreased myeloperoxidase activity, NF-κB translocation, inflammatory cytokines mRNA expression, and lipid peroxidation and increased glutathione content and superoxide dismutase and catalase activities. These results demonstrated that GC-7101 possesses strong antiulcerogenic effect by modulating oxidative stress and proinflammatory mediators.