Gastroprotective effects of the essential oil of Hyptis crenata Pohl ex Benth. on gastric ulcer models

Chemometrics of the Composition and Antioxidant Capacity of Hyptis crenata Essential Oils from Brazil

Hyptis crenata (Pohl) ex Benth is used in traditional medicine as an analgesic to treat general pain. Six Hyptis crenata samples (Hc-1 to Hc-6) were collected in Pará state, Brazil. The leaf essential oils were obtained by hydrodistillation, and GC-MS and GC-FID were used to analyze their chemical compositions. The antioxidant capacity was measured in vitro using DPPH and carotene/linoleic acid assays. Chemometrics analysis (PCA, HCA, and clustered heat map) were used to identify the sample relationships between those collected in this study and those from the literature (Hc-7 to Hc-16) samples. According to the main chemical constituents identified in the samples described in this work and the literature, the sixteen samples were classified into ten groups. Group I was characterized by 1,8-cineole (31.0%), α-pinene (13.6%), (E)-caryophyllene (7.8%), and β-pinene (7.6%); and Group IV was characterized by 1,8-cineole (17.4-23.5%), α-pinene (15.7-23.5%), β-pinene (10.5-13.4%), and limonene (8.5-9.7%). Both groups are described for the first time. The total antioxidant capacity was expressed in Trolox Equivalent Antioxidant Capacity values (TEAC): TEAC of Hc-5 (551.9 mg.TE/g) and Hc-6 (475.1 mg.TE/g). In the β-carotene/linoleic acid assay, the highest inhibition was from Hc-2 (40.0%), Hc-6 (39.0%), and Hc-3 (29.4%).

Chemical composition and antinociceptive and anti-inflammatory activity of the essential oil of Hyptis crenata Pohl ex Benth. from the Brazilian Amazon

ETHNOPHARMACOLOGICAL RELEVANCE

The leaf tea of Hyptis crenata has its practical use in the Brazilian Amazon for treating gastrointestinal and liver disorders, sweating induction, and as an anti-inflammatory.

AIM OF THE STUDY

Evaluation of the chemical composition, acute oral toxicity, and antinociceptive and anti-inflammatory activities of the H. crenata essential oil.

MATERIAL AND METHODS

The essential oil was hydrodistilled and analyzed by GC and GC-MS. The antinociceptive action in mice was evaluated for the peripheral and central analgesic activity (abdominal contortion and hot plate tests), and the xylene-induced ear swelling was carried out for the nociception test.

RESULTS

Oxygenated monoterpenes (53.0%) and monoterpene hydrocarbons (38.9%) predominated in the H. crenata oil, being 1,8-cineo1e (35.9%), α-pinene (20.8%), camphor (10.0%), and β-pinene (7.3%) their primary constituents. The oral oil administration in the mice did not display changes in behavior patterns or animal mortality at 300 and 2000 mg/kg doses. The control group's biochemical parameters (ALP, AST, ALT) displayed a statistical difference from the treated group, unlike the renal parameters, which showed no variation between the groups. Oil reduced the abdominal contortions at doses of 100 (79.5%) and 300 mg/kg (44.4%), while with endodontacin, the dose was 5 mg/kg (75.2%). In addition, the oil could not decrease the paw licking/biting time at doses of 30, 100, and 300 mg/kg. However, it showed a significant antinociceptive effect on the second phase in the formalin test inhibiting licking time, with a reduction of 50.8% (30 mg/kg), 63.4% (100 mg/kg), 58.0% (300 mg/kg), and morphine (4 mg/kg, 78.3%). The oil administration produced significant inhibition of ear edema at all tested doses, with a better effect produced at 30 mg/kg (64.0% inhibition).

CONCLUSION

The oil of Hyptis crenata, rich in 1,8-cineole, camphor, α-pinene, and β-pinene, totaling 74%, displayed low acute toxicity and significant anti-inflammatory activity, with peripheral and no central antinociceptive action. Thus, these results show an actual perspective on using H. crenata oil in developing a phytotherapeutic product.

The Essential Oil of Hyptis crenata Inhibits the Increase in Secretion of Inflammatory Mediators

Background: Hyptis crenata is a plant of great ethnopharmacological importance widely distributed in South American countries. In Northeast Brazil, teas or infusions of its aerial parts are used in folk medicine to treat several acute and chronic inflammatory diseases. In a previous work we have demonstrated that the essential oil of H. crenata (EOHc) has an antiedematogenic effect. The aim of this work was to evaluate the effect of EOHc on cytokines secretion and cellular infiltration. Methods: Peritonitis and paw edema models induced by carrageenan were used to determine leucocyte count, myeloperoxidase (MPO) activity, nitrite, and cytokines secretion. Results: EOHc (10−300 mg/kg) significantly inhibited leucocyte migration and reduced the neutrophil count (control: 1.46 × 103 ± 0.031 × 103/mL) of the total leucocytes population in extracellular exudate (control: 2.14 × 103 ± 0.149 × 103/mL) by 15.00%, 43.29%, 65.52%, and 72.83% for the doses of 10, 30, 100, and 300 mg/kg EOHc, respectively (EC50: 24.15 mg/kg). EOHc (100 mg/kg) inhibited the increase in myeloperoxidase activity and completely blocked the increase in nitrite concentration induced by carrageenan. EOHc markedly reduced the pro-inflammatory cytokines (IL-6, MCP-1, IFN-γ, TNF-α, and IL-12p70) and increased IL-10, an anti-inflammatory cytokine (compared to control group, p < 0.05). Conclusions: This study demonstrates that EOHc has a long-lasting anti-inflammatory effect mediated through interference on MPO activity, and nitrite, and cytokines secretion. This effect, coupled with low EOHc toxicity, as far as results obtained in mice could be translated to humans, suggests that EOHc has great potentiality as a therapeutic agent.

An insight into the anti-ulcerogenic potentials of medicinal herbs and their bioactive metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

Peptic ulcer disease (PUD) ranks top among the most prominent gastrointestinal problems prevalent around the world. Long-term use of non-steroidal anti-inflammatory drugs, pathogenic infection by Helicobacter pylori, imbalances between gastrointestinal regulatory factors and pathological hyperacidity are major contributors towards the development of peptic ulcers. Although synthetic drugs of multiple pharmacological classes are abundantly available, inadequacy of such agents in ensuring complete recovery in not uncommon. Therefore, pharmacological explorations of herbal products including plant extracts and their respective isolated phytoconstituents, for potential gastroprotective and antiulcer properties, are regular practice among the scientific community. Moreover, the historical preferences of a significant share of world population towards herbal-based medication over modern synthetic drugs also contribute significantly to such endeavors.

AIM OF THE REVIEW

This review has endeavored to present ethnomedicinal and pharmacological prospects of a significant number of authenticated plant species in terms of their capacity to exert gastroprotection and antiulcer activities both in vitro and in vivo. The information delineated along the way was further subjected to critical analysis to ascertain the possible future prospects of such findings into designing plant-derived products in future for the treatment of peptic ulcer.

MATERIALS AND METHODS

Electronic version of prominent bibliographic databases, including Google Scholar, PubMed, Scopus, ScienceDirect, Wiley Online Library, SpringerLink, Web of Science, and MEDLINE were explored extensively for the identification and compilation of relevant information. The plant names and respective family names were verified through the Plant List (version 1.1) and World Flora Online 2021. All relevant chemical structures were verified through PubChem and SciFinder databases and illustrated with ChemDraw Ultra 12.0.

RESULTS

A colossal number of 97 plant species categorized under 58 diverse plant families have been discussed in the review for their gastroprotective and antiulcer properties. In vivo illustrations of the pharmacological properties were achieved for almost all the species under consideration. 29 individual phytoconstituents from these sources were also characterized with similar pharmacological potentials. Majority of the plant extracts as well as their constituents were found to exert their gastroprotective effects through antioxidative pathway featuring both enzymatic and nonenzymatic mechanism. Moreover, active inhibition of acid secretion, upregulation of gastroprotective mediators and downregulation of pro-inflammatory cytokines, were also associated with a prominent number of plants or products thereof.

CONCLUSIONS

Comparative evaluations of the plant sources for their antiulcer activities, both as individual and as combination formulations, are necessary to be conducted in human subjects under properly regulated clinical conditions. Moreover, the efficacy and safety of such products should also be evaluated against those of the currently available treatment options. This will further facilitate in ascertaining their suitability and superiority, if any, in the treatment of peptic ulcer diseases. Implementation of these endeavors may eventually lead to development of more efficient treatment options in the future.

Toxic Potential of Cerrado Plants on Different Organisms

Cerrado has many compounds that have been used as biopesticides, herbicides, medicines, and others due to their highly toxic potential. Thus, this review aims to present information about the toxicity of Cerrado plants. For this purpose, a review was performed using PubMed, Science Direct, and Web Of Science databases. After applying exclusion criteria, 187 articles published in the last 20 years were selected and analyzed. Detailed information about the extract preparation, part of the plant used, dose/concentration tested, model system, and employed assay was provided for different toxic activities described in the literature, namely cytotoxic, genotoxic, mutagenic, antibacterial, antifungal, antiviral, insecticidal, antiparasitic, and molluscicidal activities. In addition, the steps to execute research on plant toxicity and the more common methods employed were discussed. This review synthesized and organized the available research on the toxic effects of Cerrado plants, which could contribute to the future design of new environmentally safe products.

Gastro-protective effect of Artemisia sieberi essential oil against ethanol-induced ulcer in rats as revealed via biochemical, histopathological and metabolomics analysis

CONTEXT

Gastric ulcer is regarded as one of the main clinical ailments with high morbidity and mortality rates.

MATERIALS AND METHODS

Gastro-protective effect of Artemisia sieberi essential oil (AS-EO) in ethanol-induced rats was evaluated via biochemical, histopathological and large-scale metabolomics analyses. Glutathione (GSH), total antioxidant capacity (TAC), prostaglandin (PGE2) and tumor necrosis factor α (TNF-α) alongside with histopathological examination of gastric mucosa were analyzed. Metabolites profiling coupled to Global Natural Products Social molecular networking platform (GNPS) and multivariate data analyses to reveal for changes in rats metabolome with treatments and involved action mechanisms.

RESULTS

Pretreatment with 100 and 200 mg/kg of AS-EO in EtOH-treated rats restored all parameters towards normal status compared to disease model. AS-EO alleviated the histological and pathological damage of gastric tissue caused by ethanol. Metabolites profiling revealed an increase in uracil, cholesterol and fatty acids/fatty acyl amides levels in ulcer rats and restored to normal levels post AS-EO intervention. These results indicated the efficacy of AS-EO in a dose-dependent manner, and to exert protective effects in ulcer rat model by targeting several metabolic pathways viz. lipid, energy, and nucleotide metabolisms.

CONCLUSION

AS-EO adds to the known uses of genus Artemisia as anti-ulcerogenic agent by attenuating oxidative stress and inflammatory responses associated with an ulcer. Several novel biomarkers for ulcer progression in rats were identified and have yet to be confirmed in human models.

The essential oil of Hyptis crenata Pohl ex Benth. presents an antiedematogenic effect in mice

Hyptis crenata, commonly known as "salva-do-Marajó", "hortelã-do-campo", and "hortelãzinha", is used in folk medicine in Northeast Brazil as tea or infusion to treat inflammatory diseases. Due to the pharmacological efficacy and the low toxicity of the essential oil of Hyptis crenata (EOHc), we decided to investigate the EOHc antiedematogenic effect in experimental models of inflammation. EOHc was administrated orally at doses of 10-300 mg/kg to male Swiss albino mice. Paw edema was induced by subcutaneous injection in the right hind paw of inflammatory stimuli (carrageenan, dextran, histamine, serotonin, and bradykinin) 60 min after administration of EOHc. EOHc significantly inhibited the induced edema. The inhibitory effect of EOHc on dextran-induced edema extended throughout the experimental time. For the 30, 100, and 300 mg/kg doses of EOHc, the inhibition was of 40.28±1.70, 51.18±2.69, and 59.24±2.13%, respectively. The EOHc inhibitory effect on carrageenan-induced edema started at 10 mg/kg at the second hour (h) and was maintained throughout the observation period. At 30, 100, and 300 mg/kg doses the inhibition started earlier, from 30 min. At the edema peak of 180 min, 56, 76, and 82% inhibition was observed for 30, 100, and 300 mg/kg doses, respectively. Additionally, the effect of EOHc on carrageenan-induced paw edema was influenced by the time of administration. The EOHc also inhibited myeloperoxidase activity. In conclusion, the EOHc showed a potent effect, both preventing and reversing the edema, consistent with its anti-inflammatory use in folk medicine.

Effects of the Hyptis martiusii Benth. leaf essential oil and 1,8-cineole (eucalyptol) on the central nervous system of mice

The aim of this study was to characterize the central effects of the Hyptis martiusii leaf essential oil (OEHM) and 1,8-cineole (eucalyptol) using behavioral animal models. Gas chromatography coupled to mass spectrometry (GC/MS) was used to characterize the chemical compounds present in the OEHM. For the behavioral tests, female Swiss mice treated with the OEHM (25, 50, 100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) were used and subjected to the following tests: open field, elevated cross maze, rotarod, sodium pentobarbital- or ethyl ether-induced sleep time, pentylenetetrazol-induced convulsions, haloperidol-induced catalepsy, and ketamine-induced hyperkinesia. GC/MS analysis identified 20 constituents with the majority of them being monoterpenes and sesquiterpenes, with eucalyptol (1,8-cineol), the major sample compound (25.93%), standing out. The results showed the OEHM (25, 50 100 and 200 mg/kg, i.p.) and its major compound (50 mg/kg, i.p.) reduced animal motility in the open field test, increased pentobarbital- and ethyl ether-induced sleep time, as well as death latency in the pentylenetetrazole-induced convulsion model. However, the tested compounds were devoid of anxiolytic-like and myorelaxant activity. In addition, the OEHM (100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) potentiated haloperidol-induced catalepsy and reduced ketamine-induced hyperkinesia. Taken together, the results suggest the OEHM has important hypnotic-sedative and antipsychotic-like effects, which appear to be due to the monoterpene 1,8-cineole, the major compound identified in the essential oil.

Antiulcer Agents: From Plant Extracts to Phytochemicals in Healing Promotion

In this narrative review, we have comprehensively reviewed the plant sources used as antiulcer agents. From traditional uses as herbal remedies, we have moved on to preclinical evidence, critically discussing the in vitro and in vivo studies focusing on plant extracts and even isolated phytochemicals with antiulcerogenic potential. A particular emphasis was also paid to Helicobacter pylori activity, with emphasis on involved mechanisms of action. Lastly, the issue of safety profile of these plant products has also been addressed.

Hepatoprotective Effect of Essential Oils from Hyptis crenata in Sepsis-Induced Liver Dysfunction

No specific therapeutics are available for the treatment of sepsis-induced liver dysfunction, a clinical complication strongly associated with the high mortality rate of septic patients. This study investigated the effect of the essential oil of Hyptis crenata (EOHc), a lamiaceae plant used to treat liver disturbances in Brazilian folk medicine, on liver function during early sepsis. Sepsis was induced by the cecal ligation and puncture (CLP) model. Rats were divided into four groups: Sham, Sham+EOHc, CLP, and CLP+EOHc. EOHc (300 mg/kg) was orally administered 12 and 24 h after surgery. The animals were sacrificed for blood collection and liver tissue samples 48 h after surgery. Hepatic function was evaluated by measuring serum bilirubin, alkaline phosphatase (ALP), aspartate aminotransferase, and alanine aminotransferase (ALT) levels. The levels of malondialdehyde and the activity of superoxide dismutase, catalase, and GSH peroxidase (GSH-Px) were measured for assessment of oxidative stress. Liver morphology was analyzed by hematoxylin and eosin staining. EOHc normalized serum ALP, ALT, and bilirubin levels and inhibited morphological changes. In addition, we observed that EOHc inhibited elevation in hepatic lipid peroxidation and reduction of the glutathione peroxidase activity induced by sepsis. Our data show that EOHc plays a protective effect against liver injury induced by sepsis.

The antiulcer effect of Cibotium barometz leaves in rats with experimentally induced acute gastric ulcer

Cibotium barometz is a pharmaceutical plant customarily used in traditional medicine in Malaysia for the treatment of different diseases, such as gastric ulcer. The gastroprotective effect of C. barometz leaves against ethanol-induced gastric hemorrhagic abrasions in Sprague Dawley rats has been evaluated in terms of medicinal properties. Seven groups of rats (normal control and ulcerated control groups, omeprazole 20 mg/kg, 62.5, 125, 250, and 500 mg/kg of C. barometz correspondingly) were used in antiulcer experiment and pretreated with 10% Tween 20. After 1 hour, the normal group was orally administered 10% Tween 20, whereas absolute alcohol was fed orally to ulcerated control, omeprazole, and experimental groups. Gastric's homogenate were assessed for endogenous enzymes activities. Stomachs were examined macroscopically and histologically. Grossly, the data demonstrated a significant decrease in the ulcer area of rats pretreated with plant extract in a dose-dependent manner with respect to the ulcerated group. Homogenates of the gastric tissue exhibited significantly increased endogenous enzymes activities in rats pretreated with C. barometz extract associated with the ulcerated control group. Histology of rats pretreated with C. barometz extract group using hematoxylin and eosin staining exhibited a moderate-to-mild disruption of the surface epithelium with reduction in submucosal edema and leucocyte infiltration in a dose-dependent manner. In addition, it showed heat shock protein70 protein up-expression and BCL2-associated X protein downexpression. These outcomes might be attributed to the gastroprotective and antioxidative effects of the plant.

Oral treatment with essential oil of Hyptis spicigera Lam. (Lamiaceae) reduces acute pain and inflammation in mice: Potential interactions with transient receptor potential (TRP) ion channels

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Hyptis comprehends almost 400 species widespread in tropical and temperate regions of America. The use of Hyptis spicigera Lam. (Lamiaceae) is reported in traditional medicine due to its gastroprotective, anti-inflammatory and analgesic properties.

AIM OF THE STUDY

The rationale of this study was to investigate the potential use of the essential oil of H. spicigera (EOHs) as analgesic.

MATERIAL AND METHODS

The antinociceptive effect of EOHs was verified analyzing acute nocifensive behavior of mice induced by chemical noxious stimuli [i.e., formalin and transient receptor potential (TRP) channels agonists]. We also verified the effects of EOHs on locomotor activity and motor performance in mice. Finally, we investigate the involvement of central afferent C-fibers with EOHs analgesic effect.

RESULTS

EOHs presented antinociceptive effect at 300 and 1000mg/kg on formalin-induced pain behavior model, presenting 50% and 72% of inhibition during the first phase (ED₅₀ =292mg/kg), and 85% and 100% during de second phase (ED₅₀ =205mg/kg), respectively. Temperature of the hind paw was reduced by EOHs treatment in a dose-dependent manner; oedema was diminished only by EOHs 1000mg/kg. EOHs does not impaired locomotor activity or motor performance. For mice injected with capsaicin, a TRPV1 activator, EOHs (1000mg/kg, ED₅₀ =660mg/kg) showed decreased (63%) nociceptive behavior. When injected with cinnamaldehyde (TRPA1 activator), mice treated with EOHs showed 23%, 43% and 66% inhibition on nociceptive behavior (100, 300 and 1000mg/kg, respectively; ED₅₀ 402mg/kg). When mice were injected with menthol (TRPM8 activator), EOHs showed 29%, 59% and 98% inhibition of nociceptive behavior (100, 300 and 1000mg/kg, respectively; with ED₅₀ =198mg/kg. Finally, when desensitized mice were injected with menthol, EOHs (300mg/kg) does not show antinociceptive effect.

CONCLUSIONS

This study demonstrated the efficacy of EOHs on experimental models of nociception. We have found the involvement of TRP channels V1, A1 and M8 with EOHs activity, which was remarkably potent and efficient in inhibiting pain evoked by menthol, a TRPM8 channel activator. TRPM8 channels from TRPV1+ C-fibers, but not TRPM8+ C-fibers nor TRPM8+ Aδ mechanosensory fibers, mediate EOHs analgesic effects.

Dhiyaaldeen S, Abdulaziz Bardi D, M. Salama S, Rouhollahi E, Karimian H, Abdolmalaki R, Azizan AHS, Mohd Ali H, Mohd Noor S, Abdulla MA. The Gastroprotective Effect of Vitex pubescens Leaf Extract against Ethanol-Provoked Gastric Mucosal Damage in Sprague-Dawley Rats

Vitex pubescens is a Malaysian therapeutic plant employed in traditional drug to remedy a variety of disorders. The purpose of this research is to assess the gastroprotective efficiency of V. pubescens leaves against ethanol-induced gastric hemorrhagic laceration in rats. Animals were randomly allocated into seven groups and pre-treated, separately, with 10% Tween 20 (normal and ulcer control groups), 20 mg/kg omeprazole (reference group), and 62.5, 125, 250, and 500 mg/kg of V. pubescens extract (experimental groups). All animals were sacrificed after another hour. Histological evaluation of the ulcer control group revealed significant injury to the gastric mucosa with edema and leucocyte infiltration of the submucosal layer. PAS staining, showed remarkably intense magenta color, remarkable increase of HSP70 and decrease of Bax proteins in rats pre-treated with plant extracts compared to the ulcer control group. Gastric homogenates revealed a remarkable increase in endogenous antioxidant enzyme activities (CAT, SOD, GSH) and a decrease in the lipid peroxidation level (MDA) in animals pre-treated with V. pubescens extract compared with the ulcer control group. The gastroprotective activity of this plant might be related to increased antioxidant enzymes and decrease lipid peroxidation upsurge of HSP70 and reduced expression of Bax proteins.

Potential protective effects of Clostridium butyricum on experimental gastric ulcers in mice

AIM: To investigate the effects of Clostridium butyricum (C. butyricum) on experimental gastric ulcers (GUs) induced by alcohol, restraint cold stress, or pyloric ligation in mice, respectively.

METHODS: One hundred and twenty mice were randomly allocated into three types of gastric ulcer models (n = 40 each), induced by alcohol, restraint cold stress, or pyloric ligation. In each GU model, 40 mice were allocated into four groups (n = 10 each): the sham control group; model group (GU induction without pretreatment); C. butyricum group (GU induction with C. butyricum pretreatment); and Omeprazole group (GU induction with Omeprazole pretreatment). The effects of C. butyricum were evaluated by examining the histological changes in the gastric mucosal erosion area, the activities of superoxide dismutase (SOD) and catalase (CAT), the level of malondialdehyde (MDA), and the contents of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, leukotriene B₄ (LTB₄) and 6-keto-PGF-1α (degradation product of PGI₂) in the gastric tissue.

RESULTS: Our data showed that C. butyricum significantly reduced the gastric mucosal injury area and ameliorated the pathological conditions of the gastric mucosa. C. butyricum not only minimized the decreases in activity of SOD and CAT, but also reduced the level of MDA in all three GU models used in this study. The accumulation of IL1-β, TNF-α and LBT₄ decreased, while 6-keto-PGF-1α increased with pretreatment by C. butyricum in all three GU models.

CONCLUSION: Our data demonstrated the protective effects of pretreatment with C. butyricum on anti-oxidation and anti-inflammation in different types of GU models in mice. Further studies are needed to explore its potential clinical benefits.

Gastroprotective effect of alpha-pinene and its correlation with antiulcerogenic activity of essential oils obtained from Hyptis species

Background:

Alpha-pinene (α-pinene) is a monoterpene commonly found in essential oils with gastroprotective activity obtained from diverse medicinal plants, including Hyptis species. The genus Hyptis (lamiaceae) consists of almost 400 species widespread in tropical and temperate regions of America. In the north and northeastern Brazil, some Hyptis species are used in traditional medicine to treat gastrointestinal disturbances.

Objective:

The present study has investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer induced by ethanol and indomethacin in mice.

Materials and Methods:

Gastric ulcers were induced in male Swiss mice (20-30 g) by oral administration of absolute ethanol or indomethacin 45 min after oral pretreatment with vehicle, standard control drugs or α-pinene (10, 30, and 100 mg/kg). One hour after the ulcerative challenges, the stomach were removed, and gastric lesions areas measured. The effects of α-pinene on the gastric juice acidity were determined by pylorus ligation model. The gastrointestinal motility and mucus depletion were determined by measuring the gastric levels of phenol red and alcian blue, respectively. Hematoxylin and eosin stained sections of gastric mucosa of the experimental groups were used for histology analysis.

Results:

α-pinene pretreatment inhibited ethanol-induced gastric lesions, reduced volume and acidity of the gastric juice and increased gastric wall mucus (P < 0.05). Furthermore, we showed an interesting correlation between concentration of α-pinene and gastroprotective effect of Hyptis species (P Pearson = 0.98).

Conclusion:

Our data showed that the α-pinene exhibited significant antiulcerogenic activity and a great correlation between concentration of α-pinene and gastroprotective effect of Hyptis species was also observed.

Identification of quinoline-chalcone hybrids as potential antiulcer agents

Antiulcer activity of novel quinoline-chalcone hybrids (13-37) was investigated. Among them, eight compounds (14, 16, 17, 23, 29, 31, 32 and 35) were found to be active in various ulcer models in Sprague-Dawley (SD) rats. To understand the mechanism of action of these hybrids, the effects of the compounds on antisecretory and cytoprotective activities were studied. All these active hybrids improved the depleted levels of mucin and consequently inhibited the formation of erosions in a pyloric ligated ulcer model. In addition, they also significantly increased the gastric PGE2 content in an aspirin induced ulcer model. The additional experiments including the in vitro metabolic stability and in vivo pharmacokinetics led to the identification of compound 17 as an orally active and safe candidate that is worthy of further investigation to be developed as an antiulcer agent.

Gastroprotective and ulcer healing effects of essential oil of Hyptis martiusii Benth. (Lamiaceae)

Hyptis martiusii Benth. is an aromatic plant found in abundance in northeastern Brazil that is used in ethnomedicine to treat gastric disorders. The aim of this study was to elucidate the mechanisms of action involved in the gastroprotection of the essential oil of Hyptis martiusii (EOHM) and to evaluate its healing capacity. Wistar rats were exposed to different protocols and subsequently were treated with 1% Tween-80 aqueous solution (negative control), pantoprazole, carbenoxolone, N-acetylcysteine (depending on the specificity of each model) or EOHM. The antisecretory activity (basal or stimulated) was determined using the pyloric ligature method. The gastroprotective action of nitric oxide and sulphydryl groups (–SH groups), as well as the quantification of adherent mucus and the levels of malondialdehyde and –SH groups in gastric mucosa, were evaluated using ethanol-induced gastric ulcer model. The healing ability was evaluated using the acetic acid-induced gastric ulcer model and histological and immunohistochemical analysis (HE, PAS and PCNA). EOHM (400 mg/kg) reduced the volume and acidity of gastric secretion stimulated by histamine and pentagastrin. The gastroprotective effect of EOHM involves the participation of endogenous sulfhydryl groups. EOHM increased mucus production (54.8%), reduced levels of MDA (72.5%) and prevented the depletion of –SH groups (73.8%) in the gastric mucosa. The treatment with EOHM reduced in 70.3% the gastric lesion area, promoting significant regeneration of the gastric mucosa, as confirmed by histological analysis and analysis of proliferating cell nuclear antigen. The results show that gastroprotective effect of EOHM is mediated by cytoprotective and antioxidant mechanisms and by their antisecretory activity, and suggest that the essential oil of Hyptis martiusii is a promising candidate for the treatment of gastric ulcers.