Menadione protects gastric mucosa against ethanol-induced ulcers

Potential Antiulcer Agents From Plants: A Comprehensive Review

Background:

Peptic ulcer is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Nowadays, several plants and compounds derived from it have been screened for their antiulcer activity. In the last few years, there has been an exponential growth in the field of herbal medicine. This field has gained popularity in both developing and developed countries because of their natural origin and less side effects.

Objective:

This review aims to provide a comprehensive summary of currently available knowledge of medicinal plants and phytoconstituents reported for their anti-ulcer properties.

Methods:

The worldwide accepted database like SCOPUS, PUBMED, SCIELO, NISCAIR, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar were used to retrieve available published literature.

Results:

A comprehensive review of the present paper is an attempt to list the plants with antiulcer activity. The review narrates the dire need to explore potential chemical moieties that exert an antiulcer effect, from unexploited traditional plants. Furthermore, the present study reveals the intense requirement to exploit the exact mechanism through which either the plant extracts or their active constituents exhibit their antiulcer properties.

Conclusion:

This article is the compilation of the plants and its constituents reported for the treatment of peptic ulcers. The Comprehensive data will surely attract the number of investigators to initiate further research that might lead to the drugs for the treatment of ulcers. As sufficient scientific data is not available on plants, most of the herbals cannot be recommended for the treatment of diseases. This can be achieved by research on pure chemical structures derived from plants or to prepare new lead compounds with proven beneficial preclinical in vitro and in vivo effects. However, a lot remains to be done in further investigations for the better status of medicinal plants.

Novokinin inhibits gastric acid secretion and protects against alcohol-induced gastric injury in rats

Novokinin (Arg-Pro-Leu-Lys-Pro-Trp), a potent vasorelaxing and hypotensive peptide modified from ovokinin, exhibits highly selective affinity for the AT₂ receptor. However, its role in gastrointestinal functions is still not fully understood. In this study, we found that novokinin inhibited basal gastric acid secretion and protected gastric mucosa from alcohol-induced injury in a dose-related manner in rats after intracerebroventricular (i.c.v.) administration. Novokinin significantly decreased basal gastric acid output at the dose of 50 and 100 nmol/rat. The effect of novokinin on gastric acid secretion was reversed by central injection of PD 123319 (10 nmol/rat), an AT₂ receptor antagonist, and peripheral injection of indomethacin (10 mg/kg), an inhibitor of prostaglandin synthesis. Meanwhile, pre-treatment with novokinin at doses of 10, 50, and 100 nmol/rat significantly reduced the alcohol-induced gastric mucosal injury compared to the ulcer-control group, which was inhibited by indomethacin (10 mg/kg). The result showed a remarkable increase in the level of prostaglandin E2 (PGE₂), glutathione (GSH), and a decrease in malondialdehyde (MDA) after i.c.v. administration of novokinin. These findings suggest that the inhibitory effect of novokinin on gastric acid secretion is probably mediated via an AT₂ receptor-prostaglandins (PGs) pathway. The gastroprotective effect of novokinin might be attributed to the inhibition of acid secretion, the cytoprotection of PGs, and the antioxidant property.

Protective effect of antioxidant rich aqueous curry leaf (Murraya koenigii) extract against gastro-toxic effects of piroxicam in male Wistar rats

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Piroxicam causes gastric ulceration through oxidative stress.

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Curry leaf extract protects against piroxicam induced gastric injury.

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Antioxidant mechanism(s) are involved in such protection.

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The extract may have future therapeutic potential.

Piroxicam (chemically 4-hydroxy-2-methyl-N-2-pyridinyl-2H-1,2-benzothiazine-3-carboxamide), a classical non-steroidal anti-inflammatory drug (NSAID) is orally administered to arthritic patients. Inhibition of prostaglandin E₂ (PGE₂) synthesis and subsequent free hydroxyl radical generation in vivo exert gastro-toxic side effects on piroxicam treatment. Leaves of curry plant are rich in antioxidants with prolific free radical scavenging activities. This led us to investigate the efficiency of the use of curry leaves in ameliorating piroxicam induced gastric damage. Piroxicam was orally (30 mg per kg body weight) administered in male albino Wistar rats to generate gastric ulcers. These rats were orally fed with graded doses of aqueous extract of curry or Murraya koenigii leaves (Cu LE) prior to piroxicam administration. Oxidative stress biomarkers, activities of antioxidant and pro-oxidant enzymes, mucin content and nature, PGE₂ level, activities of mitochondrial enzymes and histomorphology of gastric tissues were studied. Piroxicam treatment altered all the above mentioned parameters whereas, curry leaf extract pre-treated animals were protected against piroxicam induced alterations. Hence, the protective action of the antioxidant rich Cu LE was investigated to propose a new combination therapy or dietary management to arthritic patients using piroxicam.

L-Theanine healed NSAID-induced gastric ulcer by modulating pro/antioxidant balance in gastric ulcer margin

L-Theanine is a unique non-protein-forming amino acid present in tea [Camellia sinensis (L.) O. Kuntze]. In the present work, we evaluated the healing effect of L-theanine on NSAID (indomethacin)-induced gastric ulcer. Histology of the stomach tissues revealed maximum ulceration on the third day after indomethacin administration (18 mg/kg, single dose p.o.) which was accompanied by increased lipid peroxidation; protein carbonylation; Th1 cytokine synthesis, and depletion of thiol, mucin, prostaglandin (PG) E, Th2 cytokine synthesis; and total antioxidant status in mice. L-Theanine healed gastric ulcer at a dose of 10 mg/kg b.w. but aggravated the ulcerated condition at a higher dose of 40 mg/kg b.w. At 10 mg/kg b.w., L-theanine significantly alleviated the adverse oxidative effect of indomethacin through enhanced synthesis of PGE2 by modulation of cyclo-oxygenase-1 and 2 [COX-1 and COX-2] expression, Th1/Th2 cytokine balance, and restoration of cellular antioxidant status at the gastric ulcer margin. The present study revealed for the first time the dose-dependent biphasic effect of a natural neuroprotective agent, L-theanine, on gastric ulcer disease.

Menadione

This chapter includes the aspects of Menadione (vitamin K). The drug is synthesized by the use of itaconic acid obtained through Friedel-Craft condensation or by direct oxidation of the 2-methyl-1,4-naphthquinone. Vitamin K generally maintains healthy blood clotting and prevents excessive bleeding and hemorrhage, it is also important for maintaining healthy bone structure and for carbohydrate storage in the body. In addition, it is given to newborn babies born in hospitals to prevent the development of life-threatening bleeding caused by low prothrombin levels. The chapter discusses the drug metabolism and pharmacokinetics and presents various method of analysis of this drug such as compendial tests, electrochemical analysis, spectroscopic analysis, and chromatographic techniques of separation. It also discusses its physical properties such as solubility characteristics, X-ray powder diffraction pattern, and thermal methods of analysis. The chapter is concluded with a discussion on its biological properties such as activity, toxicity, and safety.

Epigallocatechin gallate accelerates healing of indomethacin-induced stomach ulcers in mice

Management of the gastric toxicity of non-steroidal anti-inflammatory drugs (NSAIDs) remains a crucial problem because the commercially available drugs have side effects and are often expensive. Therefore, we examined the potential of the green tea-derived polyphenol epigallocatechin gallate (EGCG) to treat indomethacin-induced stomach ulcers in mice. Administration of indomethacin (18 mg/kg, po) to mice induced ulceration in the glandular portion of the gastric mucosa, accompanied by increased lipid peroxidation (LPO) and protein oxidation and reductions in thiol defense, mucin, cyclooxygenase (COX) expression and prostaglandin (PG) synthesis in the gastric tissues. Daily oral administration of EGCG (2 mg/kg) or omeprazole (3 mg/kg) for 3 days produced similar (≈ 72-75%, p < 0.001) beneficial effects on the acute gastric ulceration. Treatment with the test samples partially reversed all the adverse oxidative effects of indomethacin. In addition, EGCG, but not omeprazole, enhanced expression of the COX isoforms and PG synthesis. The results suggest that the non-toxic and inexpensive tea polyphenol EGCG may be an excellent candidate for further evaluation as a potent anti-ulcer drug.

Biphasic Effect of Phyllanthus emblica L. Extract on NSAID-Induced Ulcer: An Antioxidative Trail Weaved with Immunomodulatory Effect

Amla (Phyllanthus emblica L.), apart from its food value, can be used as a gastroprotective agent in non steroidal anti-inflammatory drug (NSAID)-induced gastropathy. It has been suggested that the antioxidative property of amla is the key to its therapeutic effect. Hence, on the basis of in vitro antioxidative potential, the ethanolic extract of amla (eAE) was selected for in vivo study in NSAID-induced ulcer. Intriguingly, eAE showed biphasic activity in ulcerated mice, with healing effect observed at 60 mg/kg and an adverse effect at 120 mg/kg.The dose-dependent study revealed that switching from anti-oxidant to pro-oxidant shift and immunomodulatory property could be the major cause for its biphasic effect, as evident from the total antioxidant status, thiol concentration, lipid peroxidation, protein carbonyl content followed by mucin content, PGE₂ synthesis and cytokine status. Further, Buthionine sulfoxamine (BSO) pretreatment established the potential impact of antioxidative property in the healing action of eAE. However, eAE efficiently reduced pro-inflammatory cytokine (TNF-α and IL-1β) levels and appreciably upregulate anti-inflammatory cytokine (IL-10) concentration. In conclusion, gastric ulcer healing induced by eAE was driven in a dose-specific manner through the harmonization of the antioxidative property and modulation of anti-inflammatory cytokine level.

Black tea and theaflavins assist healing of indomethacin-induced gastric ulceration in mice by antioxidative action

The healing activities of black tea (BT) and the theaflavins (TF) against the indomethacin-induced stomach ulceration were studied in a mouse model. Indomethacin (18 mg/kg, p.o.) administration induced maximum ulceration in the glandular portion of the gastric mucosa on the 3rd day, accompanied by increased lipid peroxidation and protein oxidation, depletion of thiol-defense and mucin, as well as reduced expressions of cyclooxygenases (COX) and prostaglandin (PG) E synthesis in the gastric tissues, and plasma total antioxidant status of mice. Treatment with BT (40 mg/kg), TF (1 mg/kg), and omeprazole (3 mg/kg) produced similar (74%-76%) ulcer healing, as revealed from the histopathological studies. Treatment with all the above samples reversed the adverse oxidative effects of indomethacin significantly. BT and TF also enhanced the PGE synthesis by augmenting the expressions of COX 1 and 2, but did not modulate acid secretion.

Biochemical mechanism of healing activity of the natural phenolic, allylpyrocatechol against indomethacin-induced gastric ulceration in mice

Indomethacin caused maximum stomach ulceration in mice on the 3rd day, which was associated with reduction of plasma total antioxidant status (TAS), COX-1, COX-2, mucosal PGE(2), VEGF, and vWF, along with an increase in endostatin levels. Treatment with the phytochemical allylpyrocatechol (5 mg/kg, p.o. for 3 days) provided significant ulcer healing by reversing these biochemical parameters, as well as increasing the EGF expression more than that observed due to ulceration. Omeprazole (3 mg/kg, p.o. for 3 days) provided a similar healing by improving TAS and mucin levels, without significantly altering the other parameters.

Antiulcerogenic activity of bark extract of Tabebuia avellanedae, Lorentz ex Griseb

Tabebuia avellanedae is commonly used for the treatment of peptic ulcers. We carried out this study with the ethanolic extract of bark from Tabebuia avellanedae (EET) (30-1000 mg/kg) to determine its gastroprotective activity and to clarify the pathways involved in this effect. Acute gastric ulceration in rats was produced by oral administration of ethanol and ibuprofen. After ethanol administration, the gastric wall mucus was examined. Chronic gastric ulceration was produced by injection of acetic acid in rat gastric subserosa. Anti-secretory studies were undertaken using Shay rat pylorus ligature technique and measurement of enzymatic activity of H+, K+-ATPase in vitro. Administration of EET p.o. or i.p. significantly inhibited gastric mucosa damage induced by ethanol and ibuprofen. The anti-ulcer effect was further confirmed by enhanced gastric mucus production. In pylorus ligature rats, EET significantly reduced the basal gastric acid secretion and total acidity; moreover, it inhibited the increase in total acidity induced by histamine. In addition, EET reduced the activity of H+, K+, ATPase. The results obtained in the present pharmacological assay indicate that this plant has a protective action against gastric lesions, involving the maintenance of protective factors, such as mucus and prostaglandin, besides the reduction of gastric total acidity.

Healing potential of Picrorhiza kurroa (Scrofulariaceae) rhizomes against indomethacin-induced gastric ulceration: a mechanistic exploration

Background

The present study was undertaken to evaluate the potential of the rhizomes of the Indian medicinal plant, Picrorhiza kurroa in healing indomethacin-induced acute stomach ulceration in mice and examine its capacity to modulate oxidative stress and the levels of prostaglandin (PGE₂) and EGF during the process.

Methods

Male swiss albino mice, ulcerated with indomethacin (18 mg/kg, p. o., single dose) were treated up to 7 days with different doses of the methanol extract of P. kurroa rhizomes (designated as PK). The healing capacity of the most effective dose of PK (20 mg/kg, p. o. × 3 d) was compared with that of omeprazole (Omez) (3 mg/kg, p. o. × 3 d). The effects of the drug-treatment for one and three days on the biochemical parameters were assessed by comparing the results with that of untreated mice of the 1^st and 3^rd day of ulceration. The stomach tissues of the mice were used for the biochemical analysis.

Results

The macroscopic indices revealed maximum ulceration on the 3^rd day after indomethacin administration, which was effectively healed by PK. Under the optimized treatment regime, PK and Omez reduced the ulcer indices by 45.1% (P < 0.01), and 76.3% respectively (P < 0.001), compared to the untreated ulcerated mice.

Compared to the ulcerated untreated mice, those treated with PK for 3 days showed decreased the levels of thiobarbituric acid reactive substances (TBARS) (32.7%, P < 0.05) and protein carbonyl (37.7%, P < 0.001), and increased mucin (42.2%, P < 0.01), mucosal PGE₂ (21.4%, P < 0.05), and expressions of COX-1 and 2 (26.9% and 18.5%, P < 0.05), EGF (149.0%, P < 0.001) and VEGF (56.9%, P < 0.01). Omez reduced the TBARS (29.4%, P < 0.05), and protein carbonyl (38.9%, P < 0.001), and increased mucin (38.3%, P < 0.01), without altering the other parameters significantly.

Conclusion

PK (20 mg/kg, p. o. × 3 days) could effectively heal indomethacin-induced stomach ulceration in mice by reducing oxidative stress, and promoting mucin secretion, prostaglandin synthesis and augmenting expressions of cyclooxygenase enzymes and growth factors.

Gastroprotective properties of Myristica malabarica against indometacin-induced stomach ulceration: a mechanistic exploration

The healing activity of the methanol extract of the spice rampatri, Myristica malabarica, (RM) and omeprazole against indometacin-induced stomach ulceration has been studied in a mouse model. Treatment with RM (40 mg kg(-1) per day) and omeprazole (3 mg kg(-1) per day) for 3 days could effectively heal the stomach ulceration, as revealed from the ulcer indices and histopathological studies. Compared with the ulcerated group, treatment with RM and omeprazole for 3 days reduced the macroscopic damage score by approximately 72% and 76%, respectively (P<0.001), establishing the efficacy of RM. The extent of ulcer healing offered by 3 days' treatment with RM or omeprazole was better than that observed with natural recovery over 5 and 7 days (P<0.05). The healing capacities of RM and omeprazole could be attributed to their antioxidant activity as well as the ability to enhance the mucin content of the gastric tissues. Both drugs reduced lipid peroxidation (by 42-44%) and protein carbonyl content (by 34%), and augmented non-protein thiol levels beyond normal values. Furthermore, RM improved the mucin level beyond the normal value, while omeprazole restored it to near normalcy.

Healing properties of malabaricone B and malabaricone C, against indomethacin-induced gastric ulceration and mechanism of action

The healing activity of malabaricone B and malabaricone C, the major antioxidant constituents of the spice Myristica malabarica against the indomethacin-induced gastric ulceration in mice has been studied. The histological indices revealed maximum ulceration on the 3rd day after indomethacin administration, which was effectively healed by malabaricone B, malabaricone C (each 10 mg/kg body weight/day) and omeprazole (3 mg/kg body weight/day) for 3 days. Compared to the untreated ulcerated mice, treatment with malabaricone B, malabaricone C and omeprazole reduced the ulcer indices by 60.3% (P<0.01), 88.4% and 86.1% respectively (P<0.001). All the test samples accelerated ulcer healing than observed in natural recovery even after 7 days. Stomach ulceration reduced the total antioxidant status of plasma by 41% (P<0.05), which was significantly increased by malabaricone B (36%, P<0.01), malabaricone C (61%, P<0.001) and omeprazole (53%, P<0.001). Compared to the ulcerated untreated mice, those treated with malabaricone B reduced the levels of thiobarbituric acid reactive substances and protein carbonyls by 17% and approximately 34% respectively (P<0.05), while malabaricone C and omeprazole reduced the parameters almost equally (approximately 30%, P<0.01, and approximately 40%, P<0.01 respectively). Likewise, all the test samples reduced the oxidation of protein and non-protein thiols significantly (P<0.05). The antioxidant activity of the test samples could partly account their healing capacities. However, the differential potency of them was explainable by considering their relative abilities to modulate mucin secretion, PGE(2) synthesis and expression of EGF receptor and COX isoforms, malabaricone C being most effective in controlling all these factors.