Curcumin heals indomethacin-induced gastric ulceration by stimulation of angiogenesis and restitution of collagen fibers via VEGF and MMP-2 mediated signaling

Integrated ultra-high-performance liquid chromatography coupled with quadrupole-orbitrap mass spectrometry-based components analysis and network pharmacology strategy of Gancao Xiexin Decoction in treating gastric ulcer

Gancao Xiexin Decoction (GCXXD) is a traditional Chinese decoction that is often used in treating gastric ulcers. However, the substance basis and mechanism of action remain unclear. In this study, in vivo and in vitro components of GCXXD were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole-orbitrap mass spectrometry. The compound Discover platform was used to ultimately enable rapid identification of compounds. Acquire X intelligent data acquisition technology software was innovatively adopted. In the process of collecting drug-containing plasma, all components detected in blank plasma samples were excluded to eliminate the interference and influence of endogenous components in plasma, making the analysis results more accurate and reliable. At the same time, the possibility of selecting precursor parent ions with low concentration levels within the chromatographic peak can be increased, improving the coverage and integrality of the detection of components in vivo. Also, the targeted network pharmacology strategy combined with molecular docking was established to explore the mechanism of GCXXD in treating gastric ulcers. As a result, 113 components were identified, 41 of which could enter the bloodstream and exert therapeutic effects in vivo. The main effective components are glycyrrhizic acid, 6-gingerol, jatrorrhizine, wogonin, palmatine, and liquiritigenin, main targets in vivo were related to ALB, IL6, and VEGF, which play an important role in anti-inflammatory and promoting angiogenesis. In summary, this study adopted a comprehensive analysis strategy to reveal the pharmacodynamic material basis and mechanism of GCXXD against gastric ulcers, providing a scientific basis for its clinical application.

Micelle encapsulated curcumin and piperine-laden 3D printed calcium phosphate scaffolds enhance in vitro biological properties

Limitations in the current clinical management of critical-sized osseous defects have driven the need for multifunctional bone constructs. The ideal bone scaffold should possess advanced microarchitecture, well-defined pore interconnectivity, and supply biological signals, which actively guide and control tissue regeneration while simultaneously preventing post-implantation complications. Here, a natural medicine-based localized drug delivery from 3D printed scaffold is presented, which offers controlled release of curcumin, piperine from nano-sized polymeric micelles, and burst release of antibacterial carvacrol from the coating endowing the scaffold with their distinct, individual biological properties. This functionalized scaffold exhibits improved osteoblast (hFOB) cell attachment, 4-folds higher hFOB proliferation, and 73% increased hFOB differentiation while simultaneously providing cytotoxicity towards osteosarcoma cells with 61% lesser viability compared to control. In vitro, early tube formation (p < 0.001) indicates that the scaffolds can modulate the endothelial cellular network, critical for faster wound healing. The scaffold also exhibits 94% enhanced antibacterial efficacy (p < 0.001) against gram-positive Staphylococcus aureus, the main causative bacteria for osteomyelitis. Together, the multifunctional scaffolds provide controlled delivery of natural biomolecules from the nano-sized micelle-loaded 3D printed matrix for significant improvement in osteoblast proliferation, endothelial formation, osteosarcoma, and bacterial inhibition, guiding better bone regeneration for post-traumatic defect repair.

Treatment of Chronic Gastritis with Traditional Chinese Medicine: Pharmacological Activities and Mechanisms

Chronic gastritis (CG) is a common clinical digestive system disease, which is not easyily cured and is prone to recurrence. Traditional Chinese medicine (TCM) plays a significant role in the treatment of CG and has attracted increasing attention for clinical applications. In recent years, a large number of reports have shown that TCM has good therapeutic effect on CG. The aim of this paper is to investigate the pharmacological activities and mechanism of action of TCM in the treatment of CAG. Therefore, by searching the databases of Pubmed, China National Knowledge Infrastructure, Wanfang, and Baidu academic databases, this paper has summarized the molecular mechanisms of TCM in improving CG. The results show that the improvement of GC by TCM is closely related to a variety of molecular mechanisms, including the inhibition of Helicobacter pylori (Hp) infection, alleviation of oxidative stress, improvement of gastric function, repair of gastric mucosa, inhibition of inflammatory response, and apoptosis. More importantly, IRF8-IFN-γ, IL-4-STAT6, Hedgehog, pERK1/2, MAPK, PI3K-Akt, NF-κB, TNFR-c-Src-ERK1/2-c-Fos, Nrf2/HO-1, and HIF-1α/VEGF signaling pathways are considered as important molecular targets for TCM in the treatment of GC. These important findings will provide a direction and a basis for further exploring the pathogenesis of GC and tapping the potential of TCM in clinical treatment. This review also puts forward a bright prospect for future research of TCM in the treatment of CG.

Curcumin inhibits human leiomyoma xenograft tumor growth and induces dissolution of the extracellular matrix

OBJECTIVE

To determine whether a curcumin-supplemented diet would prevent and/or treat uterine leiomyoma growth in our mouse xenograft model.

DESIGN

Animal study.

SETTING

Laboratory study.

PATIENT(S)

N/A.

INTERVENTION(S)

Curcumin-supplemented diet.

MAIN OUTCOME MEASURE(S)

Dietary intake, blood concentrations, tumor size, extracellular matrix protein concentrations, apoptosis markers.

RESULT(S)

We found that curcumin was well tolerated as a dietary supplement, free curcumin and its metabolites were detected in the serum, and exposure resulted in approximately 60% less leiomyoma xenograft growth as well as dissolution of the peripheral extracellular matrix architecture of the xenografts. The production of matrix proteins, including collagens, decreased, whereas the number of apoptotic cells in the xenografts increased. Additionally, when xenografts were placed in a uterine intramural location, we found a significantly increased apoptotic response to curcumin in the diet.

CONCLUSION(S)

Mice on a diet supplemented with curcumin could achieve serum concentrations sufficient to regulate human leiomyoma xenograft growth, and curcumin could play both preventive and curative roles in the treatment of uterine leiomyoma as an oral nutritional supplement.

Exploring Cytokines as Potential Target in Peptic Ulcer Disease: A Systematic Update

Peptic ulcer disease (PUD) is a widespread condition that affects millions of people each year, with an incidence rate of 0.1%-1.5%, and has a significant impact on human health. A range of stimuli, such as Helicobacter pylori, non-steroidal anti-inflammatory drugs, hyperacidity, stress, alcohol, smoking, and idiopathic disease states, can produce a sore in the gastrointestinal mucosal layer. For individuals infected with H. pylori, 2%-3% remain asymptomatic throughout their life. Although PUD treatments are available, genetic variations occurring in individuals because of geographical dissimilarity and antibiotic resistance pose limitations. Specifically, inflammatory cytokine gene polymorphisms have received immense attention in recent years because they appear to affect the severity and duration of stomach inflammation, which is induced by H. pylori infection, contributing to the initiation of PUD. In such a context, in-depth knowledge of interleukins may aid in the discovery of new targets and provide precautionary approaches for the treatment of PUD. This review aims to give insights into the importance of several interleukins that cognate with PUD and contribute to ulcer progression or healing by activating or dampening the host immunity. Furthermore, the available targets with clinical evidence have been explored in this review.

Omeprazole prevents stress induced gastric ulcer by direct inhibition of MMP-2/TIMP-3 interactions

The healing of damaged tissues in gastric tract starts with the extracellular matrix (ECM) remodeling by the action of matrix metalloproteinases (MMPs). Particularly, MMP-2 (gelatinase-A) maintains ECM structure and function by degrading type IV collagen, the major component of basement membranes and by clearing denatured collagen. The proteolytic activities of MMPs are critically balanced by endogenous tissue inhibitors of metalloproteinases (TIMPs) and disruption of this balance results in several diseases. The well-known drug omeprazole is a proton pump inhibitor used for curing gastric ulcer. However, the action of omeprazole in ECM remodeling on gastroprotection has never been explored. Herein, using rat model of gastric ulcer, we report that restraint cold stress caused increase apoptosis to surface epithelia of gastric tissues along with TIMP-3 upregulation and inhibition of MMP-2 activity thereon. In contrast, omeprazole treatment suppressed TIMP-3 while increasing MMP-2 activity and thereby, restoring MMP-2/TIMP-3 balance. Additionally, nanomolar binding constant (K_d = 318 nM) of omeprazole with purified MMP-2 indicates a direct effect of omeprazole in restoring MMP-2 activity. Further in silico simulations revealed a plausible mechanism of action of omeprazole for TIMP-3 deactivation. Altogether, omeprazole restores MMP-2 activity and reduces apoptosis while preventing acute stress-induced gastric ulcer that occurs via suppression of nuclear factor kappa B (NF-κB) activity and peroxisome proliferator-activated receptor gamma activity (PPAR-γ). This represents an unprecedented correlation between physical docking of drug molecule to a protease and the severity of organ injury and provides a novel therapeutic approach to prevent stress induced tissue damage.

Melatonin rescues swim stress induced gastric ulceration by inhibiting matrix metalloproteinase-3 via down-regulation of inflammatory signaling cascade

AIM

This study investigated the link between forced swim induced acute gastric ulceration, inflammation and MMP-3 along with the possible mechanism of protective efficacy of melatonin.

MAIN METHODS

We distributed Balb/c mice into four different groups. Group 1 and 2 were given PBS gavage. Group 3 and 4 were given melatonin (60 mg/kg b.wt.) and omeprazole (25 mg/kg b.wt.), respectively, an hour prior to forced swim. Ulcer index, tissue histology, immunohistochemistry, protein carbonylation, lipid peroxidation, Myeloperoxidase, Zymography, Western blotting, reactive oxygen species (ROS), mitochondrial dehydrogenase, mitochondrial transmembrane potential and bioinformatical analysis were performed.

KEY FINDINGS

Our data revealed that gastric ulceration due to forced swim stress is responsible for overproduction of ROS, which may be a prime reason for mitochondrial dysfunction and induction of apoptosis via activation of Caspase-3. ROS is also responsible for p38 phosphorylation which in turn increases the activity of MMP-3 in ulcerated milieu, along with the oxidation of proteins, peroxidation of lipids and altered expression patterns of heat shock protein (HSP)-70. Melatonin is shown to reduce the inflammatory burden in gastric milieu and offers gastroprotection by binding to the active site of MMP-3; thereby inhibiting its activity, as suggested by in silico studies. Melatonin also inhibits the downregulation of HSP-70 and activates p38 dephosphorylation and thereby, it rescues gastric mucosal cells from stress-induced ulceration.

SIGNIFICANCE

Our findings suggest that, melatonin imparts its gastroprotective effect by down-regulating the activation of MAPK-ERK pathway along with binding to the active site of MMP-3.

Network Pharmacology and Molecular Docking Analysis on Pharmacological Mechanisms of Astragalus membranaceus in the Treatment of Gastric Ulcer

BACKGROUND

Astragalus membranaceus (AM, family: Leguminosae) exerts significant therapeutic effect on gastric ulcer (GU); however, there are scarce studies on its molecular mechanism against GU. This study aims to explore the key ingredients, key targets, and potential mechanisms of AM in the treatment of GU by utilizing network pharmacology and molecular docking.

METHODS

Several public databases were used to predict the targets of AM and GU, respectively, and the drug and disease targets were intersected to obtain the common targets. Next, the key ingredients and key targets were identified by constructing ingredient-target network and protein-protein-interaction (PPI) network. Gene Ontology biological processes (GOBP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were carried out on the common targets in order to ascertain the biological processes and signaling pathways involved. Finally, molecular docking was conducted to verify the binding affinity between the key ingredients and key targets.

RESULTS

A total of 552 predicted targets were obtained from 23 screened active ingredients, of which 203 targets were the common targets with GU. Quercetin, kaempferol, and isorhamnetin were identified as the key ingredients by constructing ingredient-target network, and TP53, AKT1, VEGFA, IL6, TNF, CASP3, and EGFR were selected as the key targets by constructing PPI network. GOBP and KEGG pathway enrichment analysis suggested that the therapeutic effect of AM on GU involved multiple biological processes and signaling pathways related to inflammation, oxidative stress, apoptosis, cell proliferation, and angiogenesis. Molecular docking validation demonstrated that all key ingredients had good binding affinity with the key targets.

CONCLUSION

This study revealed the key ingredients, key targets, and potential mechanisms of AM against GU, and these data may provide some crucial references for subsequent research and development of drugs for treating GU.

Curcumin upregulates transforming growth factor-β1, its receptors, and vascular endothelial growth factor expressions in an in vitro human gingival fibroblast wound healing model

BACKGROUND

Curcumin accelerates healing of oral wounds; however, the responsible mechanisms remain underexplored. Our hypothesis is curcumin regulates the expression of wound healing-related genes in human gingival fibroblasts (hGFs). This study investigated whether curcumin regulates transforming growth factor (TGF)-β1, type I TGF-β receptor (TGF-βRI), type II TGF-β receptor (TGF-βRII), and vascular endothelial growth factor (VEGF) expression in unwounded hGFs and an in vitro hGF wound healing model.

METHODS

The cytotoxicity of curcumin was evaluated using the MTT assay. Unwounded hGFs were treated with non-cytotoxic concentrations of curcumin for 24 h. Gene expression was determined by quantitative polymerase chain reaction. Then, hGFs were treated with 1 µM curcumin in an in vitro wound healing model. PD98059 pretreatment was performed to determine whether extracellular signal-regulated kinase (ERK) signaling was required for regulation of gene expression by curcumin.

RESULTS

Curcumin at 0.1-20 µM caused no significant change in cell viability. In unwounded hGFs, curcumin had no significant effect on TGF-β1, TGF-βRI, TGF-βRII, or VEGF expression. Conversely, curcumin significantly upregulated the expression of these genes in the in vitro wound healing model. PD98059 significantly attenuated the curcumin-stimulated TGF-βRI, TGF-βRII, and VEGF expression, whereas it had no effect on TGF-β1 expression.

CONCLUSIONS

Curcumin upregulated TGF-β1, TGF-βRI, TGF-βRII, and VEGF expression in an in vitro hGF wound healing model. The ERK pathway is required for TGF-βRI, TGF-βRII, and VEGF induction by curcumin. Our findings support the development of curcumin as a therapeutic agent for gingival ulcers.

Effect of p-cymene and rosmarinic acid on gastric ulcer healing - Involvement of multiple endogenous curative mechanisms

BACKGROUND

p-Cymene and rosmarinic acid are secondary metabolites found in several medicinal plants and spices. Previous studies have demonstrated their anti-inflammatory, antioxidant, and cytoprotective effects.

PURPOSE

To evaluate their gastroduodenal antiulcer activity, gastric healing and toxicity in experimental models.

METHODS

Preventive antiulcer effects were assessed using oral pre-treatment on HCl/ethanol-induced gastric lesions and cysteamine-induced duodenal lesions models. Gastric healing, the underlining mechanisms and toxicity after repeated doses were carried out using the acetic acid-induced gastric ulcer rat model and oral treatment for 14 days.

RESULTS

In the HCl/ethanol-induced gastric ulcer and cysteamine-induced duodenal injury, p-cymene and rosmarinic acid (50-200 mg/kg) decreased significantly the ulcer area, and so prevented lesions formation. In the acetic acid-induced ulcer model, both compounds (200 mg/kg) markedly reduced the ulcerative injury. These effects were related to an increase in the levels of reduced glutathione (GSH) and interleukin (IL)-10, and due to a decrease in malondialdehyde (MDA), IL-1β, tumor necrosis factor (TNF)-α, total and mitochondrial reactive oxygen species (ROS) levels. Downregulation of factor nuclear kappa B (NFκB) and enhanced expression of suppressor of cytokine signaling (SOCS)3 were also demonstrated. Furthermore, positive vascular endothelial growth factor (VEGF), metalloproteinase (MMP)-2, and cyclooxygenase (COX-2)-stained cells were increased in treated groups. Treatment also upregulated the platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), transforming growth factor (TGF)-β and epidermal growth factor receptor (EGFR) in gastric tissues. In isolated gastric epithelial cells this healing effect seems to be linked to a modulation of apoptosis, proliferation, survival and protein phosphorylation, such as the extracellular signal-regulated kinases (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK). Oral toxicity investigation for 14 days revealed no alterations in heart, liver, spleen, and kidneys weight nor the biochemical and hematological assessed parameters. p-Cymene and rosmarinic acid also protected animals from body weight loss maintaining feed and water intake.

CONCLUSIONS

Data altogether suggest low toxicity, antiulcer and gastric healing activities of p-cymene and rosmarinic acid. Antioxidant and immunomodulatory properties seem to be involved in the curative effect as well as the induction of different factors linked to tissue repair.

Effect of the proportion of curcuminoids on the gastroprotective action of Curcuma longa L. in rats

The gastroprotective effect of a turmeric acetone extract (TAE) (Curcuma longa L. [Zingiberaceae]) was evaluated and compared against its major curcuminoids; curcumin (CUR), demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC). Additionally, to demonstrate the importance of the metabolites' ratio in the extract on the synergistic effect, different mixtures were evaluated. An ethanol-induced gastric injury model was used to evaluate the gastroprotection activity in Wistar rats. The pharmacologic interaction analysis was performed using the Combination Index (CI)-Isobologram Equation method. The CI calculated at 0.5 of affected fraction (fa) for the TAE indicated a synergistic interaction between its components. However, when the proportion of curcuminoids changed from 3.7:1:10 in TAE to a 1:1:1 ratio, the CI implied an antagonistic effect. The binary combinations of curcuminoids (1:1) also showed an antagonistic interaction. The results of this work suggest that the proportion of curcuminoids in the TAE is crucial for the gastroprotective effect against ethanol-induced damage.

The intervention of tert-butylhydroquinone protects ethanol-induced gastric ulcer in type II diabetic rats: the role of Nrf2 pathway

Ethanol consumption increases the prevalence of gastric ulcer (GU) in rats with type II diabetes (T2D). Induction of GU by absolute ethanol (5 mL/kg or 3.94 g/kg) in the animal model resembles human ulcer characteristics. The aim was to investigate the role of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in the treatment of GU in diabetic condition. The rats were exposed to absolute ethanol 1 h before sacrifice and T2D was induced by combined exposure of high-fat diet and low dose streptozotocin. Pretreatment of tert-butylhydroquinone (tBHQ) (25 and 50 mg/kg), metformin (500 mg/kg), and omeprazole (20 mg/kg) were given once daily for last three consecutive weeks. In ethanol-exposed diabetic rats, pretreatment with tBHQ, omeprazole, and metformin reduced gastric mucosal lesion, ulcer index, histological alterations, malondialdehyde level, and apoptosis. Furthermore, the intervention of tBHQ, omeprazole, and metformin improved the integrity of the stomach mucosa, glutathione, gastric pH, collagen, and goblet cells. tBHQ treatment improved ethanol-induced alterations of Nrf2, catalase, heat shock protein 70 (HSP70), NF-κB, and endothelin-1 expressions in diabetic rats. In diabetic conditions, the incidence of GU is increased due to elevated levels of reactive oxygen species, inflammatory mediators, depleted levels of cellular antioxidants, and altered gastric parameters. The tBHQ intervention could be a rational strategy to protect these changes.

Gastroprotective Effects of Polyphenols against Various Gastro-Intestinal Disorders: A Mini-Review with Special Focus on Clinical Evidence

Polyphenols are classified as an organic chemical with phenolic units that display an array of biological functions. However, polyphenols have very low bioavailability and stability, which make polyphenols a less bioactive compound. Many researchers have indicated that several factors might affect the efficiency and the metabolism (biotransformation) of various polyphenols, which include the gut microbiota, structure, and physical properties as well as its interactions with other dietary nutrients (macromolecules). Hence, this mini-review covers the two-way interaction between polyphenols and gut microbiota (interplay) and how polyphenols are metabolized (biotransformation) to produce various polyphenolic metabolites. Moreover, the protective effects of numerous polyphenols and their metabolites against various gastrointestinal disorders/diseases including gastritis, gastric cancer, colorectal cancer, inflammatory bowel disease (IBD) like ulcerative colitis (UC), Crohn’s disease (CD), and irritable bowel syndrome (IBS) like celiac disease (CED) are discussed. For this review, the authors chose only a few popular polyphenols (green tea polyphenol, curcumin, resveratrol, quercetin), and a discussion of their proposed mechanism underpinning the gastroprotection was elaborated with a special focus on clinical evidence. Overall, this contribution would help the general population and science community to identify a potent polyphenol with strong antioxidant, anti-inflammatory, anti-cancer, prebiotic, and immunomodulatory properties to combat various gut-related diseases or disorders (complementary therapy) along with modified lifestyle pattern and standard gastroprotective drugs. However, the data from clinical trials are much limited and hence many large-scale clinical trials should be performed (with different form/metabolites and dose) to confirm the gastroprotective activity of the above-mentioned polyphenols and their metabolites before recommendation.

Brassica oleracea var. capitata L. Alleviates Indomethacin-Induced Acute Gastric Injury by Enhancing Anti-Inflammatory and Antioxidant Activity

Brassica oleracea var. capitata L. (white cabbage) is a valuable vegetable with diverse nutraceutical benefit. Present study aimed to investigate the preventive effects of B. oleracea extract (BOE) standardized by vitamin U on indomethacin (IND)-induced acute gastric injury in Sprague-Dawley rats. Pre-administration of three different doses of BOE (12.5–50 mg/kg) for 14 days significantly decreased visible ulcerative lesions in the gastric tissue. In addition, BOE alleviated IND-mediated increase in histological score with inhibiting invaded percentage of lesion and restoring mucosa thickness in peri-ulcerative region. BOE increased the gastric tissue bound to Alcian blue and inhibited the decrease in hexose, sialic acid, and collagen levels by IND, suggesting that BOE protects the gastric tissue through preserving mucus and mucosal integrity. Moreover, BOE pre-administration blocked the reduction of prostaglandin E2 and down-regulated histamine and mRNA expression related to secret gastric acid. Furthermore, BOE mitigated inflammatory responses in the gastric tissue by decreasing activity of myeloperoxidase and expression of nuclear factor-κB-dependent inflammatory genes. BOE also suppressed malondialdehyde with preventing the reduction of glutathione, superoxide dismutase, and catalase in the gastric tissue. Therefore, results from present study suggest that BOE will have a potential for preventing gastric injury.

Evaluation of curcumin-loaded polymeric nanocapsules with different coatings in chick embryo model: influence on angiogenesis, teratogenesis and oxidative stress

BACKGROUND

Curcumin (CUR) is a bioactive compound with several proven pharmacological properties. However, the major limitation for therapeutic use of CUR is its low bioavailability. In this sense, an alternative to this question is the use of polymeric nanocapsules (NC) as drug/nutraceutical delivery systems. Thus, the aim of current study was to assess the effect of CUR-loaded NC and their different coatings in chick embryo model, evaluating angiogenic, teratogenic and oxidative stress parameters.

METHODS

The physicochemical characterization of unloaded and loaded NC with different coatings: (U-NC (P80), U-NC (PEG), U-NC (EUD), U-NC (CS), CUR-NC (P80), CUR-NC (PEG), CUR-NC (EUD) and CUR-NC (CS)) were performed. After 9 days of incubation, eggs were treated (10 mL/kg eggs; via injection) with NC (unloaded and loaded with CUR) and CUR-solution. In sequence, hen's egg test-chorioallantoic membrane (HET-CAM), angiogenic assay, external abnormalities, weight of embryos and oxidative stress markers (TBARS, NPSH, ROS and CAT) were analyzed.

RESULTS

CUR-NC (P80, PEG, EUD and CS) treatments caused antiangiogenic and non-teratogenic effects in chick embryo model. Still, CUR-NC (P80), CUR-NC (PEG), CUR-NC (EUD) and CUR-NC (CS) did not alter markers of oxidative stress (TBARS, NPSH, CAT) studied. Only CUR-NC (EUD) caused increase in ROS levels.

CONCLUSION

Wherefore, these findings of present study represent a advance in research of drug/nutraceutical delivery systems.

Brassica oleracea Prevents HCl/Ethanol-Induced Gastric Damages in Mice

Brassica oleracea var. capitata L. (cabbage) is a popular vegetable with a wide range of pharmacological activities that help to promote human health. The present study investigated the beneficial effects of B. oleracea var. capitata L. extract (BOE) on HCl/ethanol (H/E)-induced gastric damages in mice. Pre-administration of BOE (25–100 mg/kg) for 7 consecutive days significantly decreased macroscopically visible lesion on the gastric mucosa induced by H/E. In addition, results from hematoxylin and eosin-stained gastric tissue showed that BOE inhibited invaded percentage of lesion and prevented the reduction in mucosal thickness in peri-ulcerative region. BOE significantly alleviated the H/E-mediated decreases in Alcian blue binding, total hexose, sialic acid, and collagen in the gastric tissue, suggesting BOE attenuates the gastric damage via preserving the integrity of gastric mucus. Moreover, BOE significantly decreased histamine level in the plasma and reduced mRNA levels associated with secreting gastric acid. Furthermore, BOE inhibited myeloperoxidase activity and suppressed nuclear factor-κB mRNA and its dependent inflammatory genes expression induced by H/E. BOE also strengthened antioxidant enzyme activity, with a mitigating H/E-mediated increase in malondialdehyde level of the gastric tissue. Thus, these results suggest that BOE has the potential to protect the gastric tissue via inhibiting gastric acid secretion, inflammation, and oxidative stress.

Malabaricone C Attenuates Nonsteroidal Anti-Inflammatory Drug-Induced Gastric Ulceration by Decreasing Oxidative/Nitrative Stress and Inflammation and Promoting Angiogenic Autohealing

Aims: Nonsteroidal anti-inflammatory drugs (NSAIDs), among the most commonly used drugs worldwide, are associated with gastrointestinal (GI) complications that severely limit the clinical utility of this essential class of pain medications. Here, we mechanistically dissect the protective impact of a natural product, malabaricone C (Mal C), on NSAID-induced gastropathy. Results: Mal C dose dependently diminished erosion of the stomach lining and inflammation in mice treated with NSAIDs with the protective impact translating to improvement in survival. By decreasing oxidative and nitrative stress, Mal C treatment prevented NSAID-induced mitochondrial dysfunction and cell death; nuclear factor κ-light-chain enhancer of activated B cell induction, release of proinflammatory cytokines and neutrophil infiltration; and disruptions in the vascular endothelial growth factor/endostatin balance that contributes to mucosal autohealing. Importantly, Mal C failed to impact the therapeutic anti-inflammatory properties of multiple NSAIDs in a model of acute inflammation. In all assays tested, Mal C proved as or more efficacious than the current first-line therapy for NSAID-dependent GI complications, the proton pump inhibitor omeprazole. Innovation: Given that omeprazole-mediated prophylaxis is, itself, associated with a shift in NSAID-driven GI complications from the upper GI to the lower GI system, there is a clear and present need for novel therapeutics aimed at ameliorating NSAID-induced gastropathy. Mal C provided significant protection against NSAID-induced gastric ulcerations impacting multiple critical signaling cascades contributing to inflammation, cell loss, extracellular matrix degradation, and angiogenic autohealing. Conclusion: Thus, Mal C represents a viable lead compound for the development of novel gastroprotective agents.

Ethanol-induced gastric ulcer in rats and intervention of tert-butylhydroquinone: Involvement of Nrf2/HO-1 signalling pathway

Gastric ulcer (GU) is the most common health concern that occurs due to alcohol consumption, smoking and physiological stress. Ethanol-induced GU in animal model resembles the pathophysiology of human ulcer. The present study was designed to investigate the cytoprotective and anti-inflammatory properties of tert-butylhydroquinone (tBHQ), a nuclear factor erythroid 2-related factor 2 (Nrf2) activator, against gastric mucosal damage induced by acute exposure of ethanol (5 ml/kg). The intervention of tBHQ (25 and 50 mg/kg, per os (po)) and omeprazole (20 mg/kg, po) was done for 10 consecutive days. Omeprazole was chosen as a standard drug because it is prescribed for the treatment of GU. Pretreatment of tBHQ decreased gastric mucosal lesion, ulcer index, apoptotic cells and lipid peroxidation level induced by ethanol. Furthermore, the intervention of tBHQ increased gastric mucosa integrity, pH, reduced glutathione, collagen and mucus-producing goblet cells. Intervention of tBHQ increased the expression of antioxidant markers such as Nrf2, haeme oxygenase-1 and catalase and decreased the expressions of inflammatory markers such as nuclear factor kappa-light-chain-enhancer of activated B cells and cyclooxygenase-2. The cytoprotective potential of tBHQ against gastric mucosal damage might be due to its ability to enhance cellular antioxidants and anti-inflammatory responses.

Mucoadhesive effect of Curcuma longa extract and curcumin decreases the ranitidine effect, but not bismuth subsalicylate on ethanol-induced ulcer model

The study of pharmacological interactions between herbal remedies and conventional drugs is important because consuming traditional herbal remedies as supplements or alternative medicine is fairly common and their concomitant administration with prescribed drugs could either have a favorable or unfavorable effect. Therefore, this work aims to determine the pharmacological interactions of a turmeric acetone extract (TAE) and its main metabolite (curcumin) with common anti-ulcer drugs (ranitidine and bismuth subsalicylate), using an ethanol-induced ulcer model in Wistar rats. The analysis of the interactions was carried out via the Combination Index-Isobologram Equation method. The combination index (CI) calculated at 0.5 of the affected fraction (fa) indicated that the TAE or curcumin in combination with ranitidine had a subadditive interaction. The results suggest that this antagonistic mechanism is associated to the mucoadhesion of curcumin and the TAE, determined by rheological measurements. Contrastingly, both the TAE and curcumin combined with bismuth subsalicylate had an additive relationship, which means that there is no pharmacological interaction. This agrees with the normalized isobolograms obtained for each combination. The results of this study suggest that mucoadhesion of curcumin and the TAE could interfere in the effectiveness of ranitidine, and even other drugs.

Exosomal MMP2 derived from mature osteoblasts promotes angiogenesis of endothelial cells via VEGF/Erk1/2 signaling pathway

The skeletal system is a dynamic organ that continuously undergoes coupled trabeculae and blood vessels remodeling, indicating the possible existence of molecular crosstalk between endothelial and osteoblastic cells. Since the cross-talk between bone-forming osteoblasts (OBs) and vessel-forming endothelial cells (ECs) have progressively gained investigators' attention, few studies focused on the regulatory function of extracellular vesicles derived from OBs on ECs. In this study, the effect of the exosomes derived from mature osteoblasts (MOBs) on the ECs was investigated. Firstly, exosomes derived from mature osteoblasts (MOB-Exos) were isolated and identified by NanoSight light scatter technology, electron microscopy and Western bolting. Fluorescent labeling of MOB-Exos revealed its internalization by ECs. RNA interference technique was used to knock down matrix metalloproteinase-2 (MMP2) in MOB-Exos. Then ECs were co-cultured with MOB-Exos and MMP2 knockdown MOB-Exos. Wound healing migration assay, transwell migration assay, CCK-8 assay and tube formation assay of ECs were conducted to determine the angiogenic capability of ECs. Then the VEGF/Erk1/2 pathway markers were detected by Western blot. Our results showed that MOB-Exos could promote the proliferation, migration and tube formation of ECs. Meanwhile, the promoted angiogenetic capacities of ECs were impaired when MMP2 in MOB-Exos was knocked down. In addition, immunoblotting indicated that MOB-Exos could promote the activation of the VEGF/Erk1/2 pathway of ECs; whereas the activation of the VEGF/Erk1/2 pathway was attenuated when the ECs were co-cultured with the MMP2 knockdown MOB-Exos. In conclusion, the MMP-2 existing in exosomes derived from MOBs could promote the angiogenesis of ECs in vitro, which might be realized through VEGF/Erk1/2 signaling pathway.

Potent therapeutic effects of ruscogenin on gastric ulcer established by acetic acid

BACKGROUND/OBJECTIVE

The present study investigated the potent therapeutic effects of Ruscogenin, main steroid sapogenin of traditional Chinese plant called 'Ophiopogon japonicas', on chronic ulcer model established with acetic acid in rats.

METHODS

24 rats were attenuated to the sham (2 ml/kg/day isotonic solution), control (untreated ulcer) and treatment (3 ml/kg/day ruscogenin) groups. After treatment for 2 weeks, gastric tissues were collected and prepared for light microscopic (H&E), immunohistochemical (Collagen I, III and IV) and biochemical analysis [Epidermal growth factor (EGF), Prostaglandin E2 (PGE2), Tumor Necrosis Factor alpha (TNF-α), Interleukin 6 and 8 (IL-6 and IL-8), Lipid Peroxidase (LPO), Myeloperoxidase (MPO), Glutathione (GSH) and Glutathione Peroxidase (GSH-Px)] and transmission electron microscopy (TEM).

RESULTS

Macroscopic scoring showed that the ulceration area of ruscogenin-treated group decreased compared with control group. Immunohistochemical analysis revealed ruscogenin ameliorated and restored the levels of Collagen I and IV to the levels of sham group. Tissue levels of EGF and PGE2 enhanced significantly in untreated ulcer group while were higher in treated ulcer group than the control group. TNF-α, IL-6, IL-8, LPO, MPO levels increased significantly in control group whereas decreased in treated rats after ruscogenin treatment. However, levels of GSH and GSH-Px increased significantly in treatment group. TEM showed chief cells and parietal cells of ulcer group having degenerated organelles while ruscogenin group had normal ultrastructure of cells.

CONCLUSION

There are potent anti-inflammatory and anti-oxidant effects of ruscogenin on gastric ulcer and may be successfully used as a safe and therapeutic agent in treatment of peptic ulcer.

Effects of Curcumin on Vessel Formation Insight into the Pro- and Antiangiogenesis of Curcumin

Curcumin is a compound extracted from the Curcuma longa L, which possesses a wide range of pharmacological effects. However, few studies have collected scientific evidence on its dual effect on angiogenesis. The present review gathered the fragmented information available in the literature to discuss the dual effect and possible mechanisms of curcumin on angiogenesis. Available information concerning the effect of curcumin on angiogenesis is compiled from scientific databases, including PubMed and Web of Science using the key term (curcumin and angiogenesis). The results were reviewed to identify relevant articles. Related literature demonstrated that curcumin has antiangiogenesis effect via regulating multiple factors, including proangiogenesis factor VEGF, MMPs, and FGF, both in vivo and in vitro, and could promote angiogenesis under certain circumstances via these factors. This paper provided a short review on bidirectional action of curcumin, which should be useful for further study and application of this compound that require further studies.

(-)-Myrtenol accelerates healing of acetic acid-induced gastric ulcers in rats and in human gastric adenocarcinoma cells

The gastroprotective property of (-)-myrtenol, a monoterpenoid, has been demonstrated previously against acute gastric ulceration induced by ethanol. However, the healing property of (-)-myrtenol in a chronic gastric ulcer model remains to be verified. This study evaluated its healing efficacy and the mechanism involved using the rat model of chronic gastric ulcer induced by serosal injection of 80% acetic acid in vivo, and human gastric adenocarcinoma cells (AGS) in vitro. The results showed that compared to vehicle-treated ulcer controls, oral administration of (-)-myrtenol (50 and 100 mg/kg/day) for 7 days promoted ulcer healing, as indicated by significant decreases in ulcer area and volume. The macroscopic and microscopic findings confirmed the healing potential of (-)-myrtenol. The ulcer healing activity was also associated with significant increases in gastric mucin content, collagen deposition, number of cells with positive marking for proliferating cell nuclear antigen (PCNA), and by changes in the expression of the inflammatory parameters tumor necrosis factor (TNF)-α, interleukin (IL)-1β and cyclooxygenase (COX)-2, as well as a decrease of metalloproteinases (MMP-9 and MMP-2) activity. Furthermore, in vitro assays using the AGS cultures revealed that (-)-myrtenol favors wound healing activity via stimulation of cell proliferation and migration without altering the cell viability. Taken together, these findings indicate that (-)-myrtenol has gastro-cytoprotective and ulcer healing properties that can be further explored to develop a new therapeutic agent from a natural source for the treatment of gastric ulcer.

Curcumin: A Potent Protectant against Esophageal and Gastric Disorders

Turmeric obtained from the rhizomes of Curcuma longa has been used in the prevention and treatment of many diseases since the ancient times. Curcumin is the principal polyphenol isolated from turmeric, which exhibits anti-inflammatory, antioxidant, antiapoptotic, antitumor, and antimetastatic activities. The existing evidence indicates that curcumin can exert a wide range of beneficial pleiotropic properties in the gastrointestinal tract, such as protection against reflux esophagitis, Barrett’s esophagus, and gastric mucosal damage induced by nonsteroidal anti-inflammatory drugs (NSAIDs) and necrotizing agents. The role of curcumin as an adjuvant in the treatment of a Helicobacter pylori infection in experimental animals and humans has recently been proposed. The evidence that this turmeric derivative inhibits the invasion and proliferation of gastric cancer cells is encouraging and warrants further experimental and clinical studies with newer formulations to support the inclusion of curcumin in cancer therapy regimens. This review was designed to analyze the existing data from in vitro and in vivo animal and human studies in order to highlight the mechanisms of therapeutic efficacy of curcumin in the protection and ulcer healing of the upper gastrointestinal tract, with a major focus on addressing the protection of the esophagus and stomach by this emerging compound.

Curcumin in tissue engineering: A traditional remedy for modern medicine

Curcumin is the principal polyphenolic compound present in turmeric with broad applications in tissue engineering and regenerative medicine. It has some important inherent properties with the potential to facilitate tissue healing, including anti-inflammatory, anti-oxidant, and antibacterial activities. Therefore, curcumin has been used for the treatment of various damaged tissues, especially wound injuries. There are different forms of curcumin, among which nano-formulations are of a great importance in regenerative medicine. It is also important to design sophisticated delivery systems for controlled/localized delivery of curcumin to the target tissues and organs. Although there are many reports on the advantages of this compound, further research is required to fully explore its clinical usage. The review describes the physicochemical and biological properties of curcumin and the current state of the evidence on its applications in tissue engineering. © 2018 BioFactors, 45(2):135-151, 2019.

Cellular and molecular mechanisms of curcumin in prevention and treatment of disease

Curcumin is a naturally occurring polyphenolic compound present in rhizome of Curcuma longa belonging to the family zingiberaceae. Growing experimental evidence revealed that curcumin exhibit multitarget biological implications signifying its crucial role in health and disease. The current review highlights the recent progress and mechanisms underlying the wide range of pharmacological effects of curcumin against numerous diseases like neuronal, cardiovascular, metabolic, kidney, endocrine, skin, respiratory, infectious, gastrointestinal diseases and cancer. The ability of curcumin to modulate the functions of multiple signal transductions are linked with attenuation of acute and chronic diseases. Numerous preclinical and clinical studies have revealed that curcumin modulates several molecules in cell signal transduction pathway including PI3K, Akt, mTOR, ERK5, AP-1, TGF-β, Wnt, β-catenin, Shh, PAK1, Rac1, STAT3, PPARγ, EBPα, NLRP3 inflammasome, p38MAPK, Nrf2, Notch-1, AMPK, TLR-4 and MyD-88. Curcumin has a potential to prevent and/or manage various diseases due to its anti-inflammatory, anti-oxidant and anti-apoptotic properties with an excellent safety profile. In contrast, the anti-cancer effects of curcumin are reflected due to induction of growth arrest and apoptosis in various premalignant and malignant cells. This review also carefully emphasized the pharmacokinetics of curcumin and its interaction with other drugs. Clinical studies have shown that curcumin is safe at the doses of 12 g/day but exhibits poor systemic bioavailability. The use of adjuvant like piperine, liposomal curcumin, curcumin nanoparticles and curcumin phospholipid complex has shown enhanced bioavailability and therapeutic potential. Further studies are warranted to prove the potential of curcumin against various ailments.

Effect of curcumin on tendon healing: an experimental study in a rat model of Achilles tendon injury

PURPOSE

This in vivo study aims to investigate the effects of curcumin which is recently developed for tendon healing using a rat Achilles tendon injury model.

MATERIALS AND METHODS

Eighteen male Wistar albino rats weighing 300-400 g were used in this study. Under anesthesia, Achilles tendon injuries were created and repaired surgically. Nine rats of the study group received curcumin (suspended in saline at a dose of 200 mg/kg orally) and eight rats of the control group received only saline solution by oral gavage for a period of 28 days. Animals were euthanized on the 28th post-operative day, and all the Achilles tendons were removed and transferred immediately for biomechanic and histological analysis.

RESULTS

Macroscopically, all the tendons were fully healed. Total mean Bonar score was higher in the control group. When the parameters of Bonar score were analysed separately, tenocyte morphology, collogen, and ground substance scores were statistically lower than the control group (p = 0.03, 0.041, 0.049, respectively). Vascularity parameter did not show any statistical difference (p > 0.05). Of the nine biomechanical parameters, five of them (failure load, cross-sectional area, length, ultimate stress, strain) showed better results which were also statistically significant (p = 0.046, 0.027, 0.011, 0.021, 0.002, respectively). When the remaining four parameters were examined, the study group also had better results, but this difference was not statistically significant.

CONCLUSION

Curcumin had better results for total tendon healing not only histologically but also biomechanically. Curcumin could be an additional agent in the management of surgically repaired tendon injuries.

Combination therapy with polydeoxyribonucleotide and proton pump inhibitor enhances therapeutic effectiveness for gastric ulcer in rats

AIMS

The main action of proton pump inhibitors (PPIs) is to inhibit gastric acid secretion, and PPIs are widely used to treat gastric ulcer (GU). However, if the action of promoting gastric mucosal regeneration is added, the effectiveness of GU treatment can be enhanced. Thus, in order to improve the therapeutic effect on GU, we tried to develop combination therapy promoting regeneration in injured tissue besides suppressing gastric acid secretion.

MAIN METHODS

Polydeoxyribonucleotide (PDRN) was selected to evaluate tissue regeneration, and pantoprazole was chosen as one of the PPIs. GU was induced by oral administration of indomethacin once a day for 7 days. Rats in drug-administered groups were intraperitoneally injected with 100 μL normal saline, containing each drug at the indicated concentration, once a day for 14 days after inducing GU.

KEY FINDINGS

PDRN and PPI combination therapy potently improved tissue regeneration and inhibited production of pro-inflammatory cytokines. PDRN treatment with or without PPI increased the concentration of cyclic adenosine-3,5'-monophosphate (cAMP) and the ratio of phosphorylated cAMP response element-binding protein (p-CREB) to cAMP response element-binding protein (CREB). PDRN treatment with or without PPI also increased the expressions of vascular endothelial growth factor (VEGF) and adenosine A_2A receptor.

SIGNIFICANCE

PDRN and PPI combination therapy showed more potent therapeutic effect on GU compared to the PDRN monotherapy or PPI monotherapy. The excellent therapeutic effect of PDRN and PPI combination therapy on GU appeared by promoting regeneration of damaged tissue as well as inhibiting gastric acid secretion.

The Effects of Methanolic Extract of Melissa officinalis on Experimental Gastric Ulcers in Rats

BACKGROUND

Melissa officinalis (MO) has potent antioxidant activity. Recent research has demonstrated the anti-ulcer properties of some medicinal plants through their antioxidant properties.

OBJECTIVES

The aim of this study was to evaluate the effects of methanolic extracts of MO on experimental gastric ulcers in rats.

MATERIALS AND METHODS

Male Wistar rats (200 - 250 g) were starved for 24 hours prior to the induction of gastric ulceration by either indomethacin (48 mg/kg/oral) or water immersion restraint (WIR) stress. Experimental rats received either ranitidine (25 mg/kg) or MO extract (150, 300 and 450mg/kg) orally 2 hours prior to WIR stress or indomethacin treatment, for the evaluation of their gastroprotective effects. The control group received the same volume of saline. Gastric lesions were scored according to the surface of lesions on the ulcer index. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) were determined as measures of antioxidant defense, and malondialdehyde (MDA) was determined to measure tissue oxidation.

RESULTS

MO extract (150 and 300 mg/kg) significantly decreased the ulcer index in both the indomethacin (1.3 ± 0.09 and 1.5 ± 0.19, respectively) and WIR stress groups (1.5 ± 0.17 and 1.5 ± 0.22, respectively), as compared to the control rats (2.5 ± 0.28) (P < 0.01). MO extract (450 mg/kg) significantly reduced ulcer index readings in WIR stress rats (1.8 ± 0.31 vs. 2.4 ± 0.15 in the WIR group), however, MO extract at a dose of 450 mg/kg did not prevent indomethacin-induced gastric ulceration (2.4 ± 0.26). There was no significant difference in the ulcer index for MO extract- (150 and 300 mg/kg) and ranitidine-treated rats (P > 0.05). Also, MO extract (150 and 300 mg/kg) significantly reduced MDA serum levels (0.69 ± 0.6 µmol/L and 0.85 ± 0.24 µmol/L, respectively, vs. 4.5 ± 1.9 µmol/L in the saline group) and significantly increased antioxidants' SOD activities (296.3 ± 146.4 U/mL and 561.4 ± 120 U/mL, respectively, vs. 190.2 ± 63.8U/mL in the control group) and GPX levels (8273 ± 3049 U/mL and 14574 ± 5012 U/mL, respectively), compared to the control (3236 ± 1699 U/mL).

CONCLUSIONS

Our results showed that MO extract may have a gastroprotective effect against experimental gastric ulcers in rats. The exact mechanism has not yet been determined, but it may be due to enhancing enzymatic antioxidant defenses and inhibiting lipid peroxidation.

Phytochemicals in Wound Healing

Significance: Traditional therapies, including the use of dietary components for wound healing and skin regeneration, are very common in Asian countries such as China and India. The increasing evidence of health-protective benefits of phytochemicals, components derived from plants is generating a lot of interest, warranting further scientific evaluation and mechanistic studies. Recent Advances: Phytochemicals are non-nutritive substances present in plants, and some of them have the potential to provide better tissue remodeling when applied on wounds and to also act as proangiogenic agents during wound healing. Critical Issues: In this review, we briefly discuss the current understanding, important molecular targets, and mechanism of action(s) of some of the phytochemicals such as curcumin, picroliv, and arnebin-1. We also broadly review the multiple pathways that these phytochemicals regulate to enhance wound repair and skin regeneration. Future Directions: Recent experimental data on the effects of phytochemicals on wound healing and skin regeneration establish the potential clinical utility of plant-based compounds. Additional research in order to better understand the exact mechanism and potential targets of phytochemicals in skin regeneration is needed. Human studies a2nd clinical trials are pivotal to fully understand the benefits of phytochemicals in wound healing and skin regeneration.

Matrix metalloproteinase 14 modulates signal transduction and angiogenesis in the cornea

The cornea is transparent and avascular, and retention of these characteristics is critical to maintaining vision clarity. Under normal conditions, wound healing in response to corneal injury occurs without the formation of new blood vessels; however, neovascularization may be induced during corneal wound healing when the balance between proangiogenic and antiangiogenic mediators is disrupted to favor angiogenesis. Matrix metalloproteinases (MMPs), which are key factors in extracellular matrix remodeling and angiogenesis, contribute to the maintenance of this balance, and in pathologic instances, can contribute to its disruption. Here, we elaborate on the facilitative role of MMPs, specifically MMP-14, in corneal neovascularization. MMP-14 is a transmembrane MMP that is critically involved in extracellular matrix proteolysis, exosome transport, and cellular migration and invasion, processes that are critical for angiogenesis. To aid in developing efficacious therapies that promote healing without neovascularization, it is important to understand and further investigate the complex pathways related to MMP-14 signaling, which can also involve vascular endothelial growth factor, basic fibroblast growth factor, Wnt/β-catenin, transforming growth factor, platelet-derived growth factor, hepatocyte growth factor or chemokines, epidermal growth factor, prostaglandin E2, thrombin, integrins, Notch, Toll-like receptors, PI3k/Akt, Src, RhoA/RhoA kinase, and extracellular signal-related kinase. The involvement and potential contribution of these signaling molecules or proteins in neovascularization are the focus of the present review.

Curcumin improves tendon healing in rats: a histological, biochemical, and functional evaluation

Curcumin, a compound extracted from the roots of Zingiberaceae, has been proposed as a treatment for tissue injury but studies are yet to be done on its effect on tendon healing. Therefore, we performed a series of experiments to test our hypothesis that curcumin has positive effects on tendon repair. Patellar tendon window defect was created in Sprague-Dawley rats and these were divided into two groups: (i) control and (ii) curcumin-treated. Curcumin (100 mg/kg body weight) was applied by oral gavage. Its potential for promoting tendon healing was assessed by histological evaluation, mRNA expression of tenocyte-related genes, malondialdehyde (MDA) levels, manganese-dependent superoxide dismutase (MnSOD) activity, quantification of hydroxyproline (HOPro), and biomechanical testing. In this tendon injury model, curcumin significantly improved the healing properties as evidenced by extensive deposition of well-organized collagen fibers, decreased MDA levels, and increase in the biomechanical properties and MnSOD activity of the regenerated tendon tissues. The current study showed that curcumin can improve the quality of tendon rupture healing, and thus represents a promising strategy in the management of injured tendon tissue.

Role of dietary polyphenols in the management of peptic ulcer

Peptic ulcer disease is a multifactorial and complex disease involving gastric and duodenal ulcers. Despite medical advances, the management of peptic ulcer and its complications remains a challenge, with high morbidity and death rates for the disease. An accumulating body of evidence suggests that, among a broad reach of natural molecules, dietary polyphenols with multiple biological mechanisms of action play a pivotal part in the management of gastric and duodenal ulcers. The current review confirmed that dietary polyphenols possess protective and therapeutic potential in peptic ulcer mediated by: improving cytoprotection, re-epithelialization, neovascularization, and angiogenesis; up-regulating tissue growth factors and prostaglandins; down-regulating anti-angiogenic factors; enhancing endothelial nitric oxide synthase-derived NO; suppressing oxidative mucosal damage; amplifying antioxidant performance, antacid, and anti-secretory activity; increasing endogenous mucosal defensive agents; and blocking Helicobacter pylori colonization associated gastric morphological changes and gastroduodenal inflammation and ulceration. In addition, anti-inflammatory activity due to down-regulation of proinflammatory cytokines and cellular and intercellular adhesion agents, suppressing leukocyte-endothelium interaction, inhibiting nuclear signaling pathways of inflammatory process, and modulating intracellular transduction and transcription pathways have key roles in the anti-ulcer action of dietary polyphenols. In conclusion, administration of a significant amount of dietary polyphenols in the human diet or as part of dietary supplementation along with conventional treatment can result in perfect security and treatment of peptic ulcer. Further well-designed preclinical and clinical tests are recommended in order to recognize higher levels of evidence for the confirmation of bioefficacy and safety of dietary polyphenols in the management of peptic ulcer.

Curcumin-induced angiogenesis hastens wound healing in diabetic rats

BACKGROUND

Neovasculogenesis, vital for wound healing, gets compromised in diabetics patients, which consequently delayed wound healing. Previous studies have shown curcumin as both a stimulatory and an inhibitory agent in the neovasculogenesis process. So, present study was aimed to investigate the effects of curcumin on wound healing in diabetic rats and to explore the expressions of the various factors involved in neovasculogenesis.

MATERIALS AND METHODS

Open excisional diabetic wound was created in sixty rats and divided into three groups viz. i) control, ii) pluronic gel-treated, and iii) curcumin-treated. The pluronic F-127 gel (25%) and curcumin (0.3%) in the pluronic gel were topically applied once daily for 19 d. The wound healing and neovasculogenesis among these groups were evaluated by gross appearance of wounds and microscopically by hematoxylin and eosin staining, immunohistochemistry for CD31, messenger RNA expressions of vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β1, hypoxia-inducible growth factor-1 alpha, stromal cell-derived growth factor-1 alpha, and heme oxygenase-1, and Western blotting studies of VEGF and TGF-β1 in granulation and/or healing tissue on days 3, 7, 14, and 19.

RESULTS

Curcumin application caused markedly fast wound closure with well-formed granulation tissue dominated by fibroblast proliferation, collagen deposition, and complete early regenerated epithelial layer. Immunohistochemistry for CD31 revealed well-formed blood vessels with increased microvessel density on days 3, 7, and 14 in the curcumin-treated group. Expressions of VEGF and TGF-β1 on days 3, 7, and 14, hypoxia-inducible growth factor-1 alpha, stromal cell-derived growth factor-1 alpha, and heme oxygenase-1 on days 3 and 7 were increased in curcumin-treated diabetic rats, as compared with other groups.

CONCLUSIONS

Curcumin enhanced the neovasculogenesis and accelerated the wound healing in diabetic rats by increased expressions of various factors.

Inactivation of FoxM1 transcription factor contributes to curcumin-induced inhibition of survival, angiogenesis, and chemosensitivity in acute myeloid leukemia cells

Aberrant expression of forkhead box protein M1 (FoxM1) contributes to carcinogenesis in human cancers, including acute myeloid leukemia (AML), suggesting that the discovery of specific agents targeting FoxM1 would be extremely valuable for the treatment of AML. Curcumin, a naturally occurring phenolic compound, is suggested to possess anti-leukemic activity; however, the underlying mechanism has not been well elucidated. In this study, we found that curcumin inhibited cell survival accompanied by induction of G2/M cell cycle arrest and apoptosis in HL60, Kasumi, NB4, and KG1 cells. This was associated with concomitant attenuation of FoxM1 and its downstream genes, such as cyclin B1, cyclin-dependent kinase (CDK) 2, S-phase kinase-associated protein 2, Cdc25B, survivin, Bcl-2, matrix metalloproteinase (MMP)-2, MMP-9, and vascular endothelial growth factor (VEGF), as well as the reduction of the angiogenic effect of AML cells. We also found that specific downregulation of FoxM1 by siRNA prior to curcumin treatment resulted in enhanced cell survival inhibition and induction of apoptosis. Accordingly, FoxM1 siRNA increased the susceptibility of AML cells to doxorubicin-induced apoptosis. More importantly, curcumin suppressed FoxM1 expression, selectively inhibited cell survival as well as the combination of curcumin and doxorubicin exhibited a more inhibitory effect in primary CD34(+) AML cells, while showing limited lethality in normal CD34(+) hematopoietic progenitors. These results identify a novel role for FoxM1 in mediating the biological effects of curcumin in human AML cells. Our data provide the first evidence that curcumin together with chemotherapy or FoxM1 targeting agents may be effective strategies for the treatment of AML.

KEY MESSAGE

Curcumin inhibited AML cell survival and angiogenesis and induced chemosensitivity. Aberrant expression of FoxM1 induces AML cell survival and chemoresistance. Inactivation of FoxM1 contributes to curcumin-induced anti-leukemic effects. Curcumin together with FoxM1 targeting agents may be effective for AML therapy.

Pharmacological evidence for the participation of NO-cGMP-KATP pathway in the gastric protective effect of curcumin against indomethacin-induced gastric injury in the rat

Curcumin, main compound obtained from rizhoma of Curcuma longa, shows antitumoral, antioxidant, anticarcinogenic and gastric protective properties. Recently, it has been demonstrated that curcumin exerts its gastric protective action due to an increase in gastric nitric oxide (NO) levels. However, it is unknown whether these increased NO levels are associated with activation of intracellular signaling pathways. Thus, the purpose of this study was to investigate the role of NO-cGMP-KATP pathway in the gastric protective effect of curcumin during indomethacin-induced gastric injury in the rat. Adult female Wistar rats were gavaged with curcumin (3-300mg/kg, p.o.) or omeprazole (30mg/kg, p.o.) 30min before indomethacin insult (30mg/kg, p.o.). Other groups of rats were administered L-NAME (70mg/kg, i.p.; inhibitor of nitric oxide synthase), ODQ (10mg/kg, i.p.; inhibitor of soluble guanylate cyclase) or glibenclamide (1mg/kg, i.p.; blocker of ATP-sensitive potassium (KATP) channels) 30min before curcumin (30mg/kg, p.o.). 3h after indomethacin administration, rats were sacrificed and gastric injury was evaluated by determining total damaged area. A sample of gastric tissue was harvested and processed to quantify organic nitrite levels. Curcumin significantly protected against indomethacin-induced gastric injury and this effect was comparable to gastroprotective effect by omeprazole. L-NAME, ODQ and glibenclamide significantly prevented the curcumin-mediated gastric protective effect in the indomethacin-induced gastric injury model. Furthermore, curcumin administration induced a significant increase in gastric nitric oxide levels as compared to vehicle administration. Our results show for the first time that curcumin activates NO/cGMP/KATP pathway during its gastro protective action.