Mohd Fahami Nur Azlina

The effects of palm vitamin E on stress hormone levels and gastric lesions in stress-induced rats

Introduction This study examines the effects of palm vitamin E (PVE) or α-tocopherol (α-TF) supplementation on adrenocorticotropin hormone (ACTH), corticosterone and gastric lesions in rats exposed to water-immersion restraint stress (WIRS). Material and methods Sixty male Sprague-Dawley rats (200-250 g) were divided into three groups. Group I: 20 rats as a control group were given a normal diet. Group II: 20 rats received oral supplementation of PVE at 60 mg/kg body weight. Group III: 20 rats received oral supplementation of α-TF at 60 mg/kg body weight. After the treatment period of 28 days, each group was further subdivided into two groups: 10 rats not exposed to stress, and the other 10 rats subjected to WIRS for 3.5 h. Blood samples were taken to measure the ACTH and corticosterone levels. The rats were then sacrificed and the stomach excised and opened along the greater curvature and examined for lesions. Results Rats exposed to WIRS had lesions in their stomach mucosa. Our findings showed that dietary supplementation of PVE or α-TF was able to reduce gastric lesions significantly in comparison to the stressed controls. The WIRS increased plasma ACTH and corticosterone significantly. Palm vitamin E and α-TF treatments reduced these parameters significantly compared to the stressed controls. Conclusions Supplementation with either PVE or α-TF reduces the formation of gastric lesions, probably by inhibiting the elevation of ACTH and corticosterone levels induced by stress.

Tocotrienol Attenuates Stress-Induced Gastric Lesions via Activation of Prostaglandin and Upregulation of COX-1 mRNA

The present study aims to distinguish the effect of tocotrienol on an important gastric protective factor, prostaglandin E2 (PGE2), in stress-induced gastric injury. Twenty-eight Wistar rats were divided into four groups of seven rats each. Two control groups were fed commercial rat diet, and two treatment groups were fed the same diet but with additional dose of omeprazole (20 mg/kg) or tocotrienol (60 mg/kg). After 28 days, rats from one control group and both treated groups were subjected to water-immersion restraint stress for 3.5 hours once. The rats were then sacrificed, their stomach isolated and gastric juice collected, lesions examined, and gastric PGE2 content and cyclooxygenase (COX) mRNA expression were determined. Both the regimes significantly attenuated the total lesion area in the stomach compared to the control. Gastric acidity, which was increased in stress, was significantly reduced in rats supplemented with omeprazole and tocotrienol. The PGE2 content was also significantly higher in the rats given tocotrienol supplementation compared to the control followed by an increase in COX-1 mRNA expression. We conclude that tocotrienol supplementation protected rat gastric mucosa against stress-induced lesions possibly by reducing gastric acidity and preserving gastric PGE2 by increasing COX-1 mRNA.

Vitamin E: A potential therapy for gastric mucosal injury

Abstract Context: Many scientific reports have shown the involvement of oxidative stress and inflammation as well as diminished gastroprotective substances in the pathogenesis of gastric lesions using various models. Therefore, treatment with antioxidants like tocopherol and tocotrienol may afford beneficial effects in attentuating the formation of the gastric lesions. Objective: The aim of this work was to summarize documented reports on the effects of vitamin E on various models of gastric lesion. Methods: A literature search was performed from databases in Medline (PubMed), Web of Science, ScienceDirect, and Googlescholar from June to December 2013. Results and conclusion: The potential roles of tocopherol and tocotrienol in modifying the effects of ulcerogenic agents are discussed in this review. The protective effects of the vitamin E might involve ameliorating oxidative stress and inflammation as well as restoration of endogenous gastroprotective substances. This vitamin has the potential to be used as a therapy for gastric mucosal injury.

Preventive Effects of Tocotrienol on Stress-Induced Gastric Mucosal Lesions and Its Relation to Oxidative and Inflammatory Biomarkers

This study aimed to investigate the possible gastroprotective effect of tocotrienol against water-immersion restraint stress (WIRS) induced gastric ulcers in rats by measuring its effect on gastric mucosal nitric oxide (NO), oxidative stress, and inflammatory biomarkers. Twenty-eight male Wistar rats were randomly assigned to four groups of seven rats. The two control groups were administered vitamin-free palm oil (vehicle) and the two treatment groups were given omeprazole (20 mg/kg) or tocotrienol (60 mg/kg) orally. After 28 days, rats from one control group and both treated groups were subjected to WIRS for 3.5 hours once. Malondialdehyde (MDA), NO content, and superoxide dismutase (SOD) activity were assayed in gastric tissue homogenates. Gastric tissue SOD, iNOS, TNF-α and IL1-β expression were measured. WIRS increased the gastric MDA, NO, and pro-inflammatory cytokines levels significantly when compared to the non-stressed control group. Administration of tocotrienol and omeprazole displayed significant protection against gastric ulcers induced by exposure to WIRS by correction of both ulcer score and MDA content. Tissue content of TNF-α and SOD activity were markedly reduced by the treatment with tocotrienol but not omeprazole. Tocotrienol significantly corrected nitrite to near normal levels and attenuated iNOS gene expression, which was upregulated in this ulcer model. In conclusion, oral supplementation with tocotrienol provides a gastroprotective effect in WIRS-induced ulcers. Gastroprotection is mediated through 1) free radical scavenging activity, 2) the increase in gastric mucosal antioxidant enzyme activity, 3) normalisation of gastric mucosal NO through reduction of iNOS expression, and 4) attenuation of inflammatory cytokines. In comparison to omeprazole, it exerts similar effectiveness but has a more diverse mechanism of protection, particularly through its effect on NO, SOD activity, and TNF-α.

Antiulcer Effect of Honey in Nonsteroidal Anti-Inflammatory Drugs Induced Gastric Ulcer Model in Rats: A Systematic Review

Background Peptic ulcer is a basic term for ulcers on the lower oesophagus, stomach, or jejunum. The specific term for ulcer in the stomach is gastric ulcer. The extensive use of honey around the globe helps researchers to study the usefulness of honey. Many studies had already been conducted and proved the effectiveness of honey in treating gastric ulcer. Methods A systematic review of the literature was conducted to identify relevant studies on honey used as an alternative treatment of gastric ulcer cause by NSAIDs. A comprehensive search was conducted in Medline, SCOPUS, and Ebscohost. The main criteria used were articles published in English and using NSAIDs-induced gastric ulcer in rats model and those reporting the effectiveness of honey. Results Articles published between 2001 and 2014 were identified to be relevant in studies related to the inclusion criteria. The literature search found 30 potential and closely related articles in this review, but only 5 articles were taken which meet the criteria needed to be fulfilled. Conclusions All studies in this review reported the efficacy of honey for gastric ulcer based on its antioxidant and cytoprotective activities. Most of the studies conducted used different types of honey at various doses on rats. Future studies should be conducted to identify the appropriate dose for humans to achieve similar gastroprotective effects.

Comparison between tocotrienol and omeprazole on gastric growth factors in stress-exposed rats

AIM To investigate and compare the effects of tocotrienol and omeprazole on gastric growth factors in rats exposed to water-immersion restraint stress (WIRS). METHODS Twenty-eight male Wistar rats were randomly assigned to four groups of seven rats. The two control groups were administered vitamin-free palm oil (vehicle) and the two treatment groups were given omeprazole (20 mg/kg) or tocotrienol (60 mg/kg) by oral gavage. After 28 d of treatment, rats from one control group and both treated groups were subjected to WIRS one time for 3.5 h. Gastric lesions were measured and gastric tissues were obtained to measure vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and transforming growth factor-alpha (TGF-α) mRNA expression. RESULTS Rats exposed to WIRS for 3.5 h demonstrated the presence of considerable ulcers in the form of gastric erosion. The lesion index in the stressed control (S) group was increased (P < 0.001) compared to the tocotrienol treated and omeprazole treated groups. Stress led to a decrease in gastric VEGF (P < 0.001), bFGF (P < 0.001) and TGF-α (P < 0.001) mRNA levels and caused an increase in EGF mRNA (P < 0.001) that was statistically significant compared to the non-stressed control group. Although both treatment agents exerted similar ulcer reducing ability, only treatment with tocotrienol led to increased expression of VEGF (P = 0.008), bFGF (P = 0.001) and TGF-α (P = 0.002) mRNA. CONCLUSION Tocotrienol provides gastroprotective effects in WIRS-induced ulcers. Compared to omeprazole, tocotrienol exerts a similar protective effect, albeit through multiple mechanisms of protection, particularly through up-regulation of growth factors that assist in repair of gastric tissue injuries.

Tocopherol And Tocotrienol: Therapeutic Potential In Animal Models of Stress

BACKGROUND Scientific reports had shown that stress is related to numerous pathological changes in the body. These pathological changes can bring about numerous diseases and can significantly cause negative effects in an individual. These include gastric ulcer, liver pathology and neurobehavioral changes. A common pathogenesis in many diseases related to stress involves oxidative damage. Therefore, the administration of antioxidants such as vitamin E is a reasonable therapeutic approach. However, there is conflicting evidence about antioxidant supplementation. OBJECTIVE The aim of this work was to summarize documented reports on the effects of tocopherol and tocotrienol on various pathological changes induced by stress. RESULTS AND CONCLUSION This review will reveal the scientific evidence of enteral supplementation of vitamin E in the forms of tocotrienol and tocopherol in animal models of stress. These models mimic the stress endured by critically ill patients in a clinical setting and psychological stress in individuals. Positive outcomes from enteral feeding of vitamin E in reducing the occurrence of stress-induced pathological changes are discussed in this review. These positive findings include their ability to reduced stress-induced gastric ulcers, elevated liver enzymes and improved locomotors activity. Evidences showing tocotrienol and tocopherol effects are not just related to its ability to reduce oxidative stress but also acting on other mechanism, are discussed.

In vivo effect of Piper sarmentosum methanolic extract on stress-induced gastric ulcers in rats

Introduction Piper sarmentosum (Piperaceae) is traditionally used by Asians to treat numerous common ailments including asthma, fever and gastritis. The aim of the research was to determine and compare the effects of Piper sarmentosum (PS) with omeprazole (OMZ) on gastric parameters in rats exposed to restraint stress. Material and methods The methanolic extract of PS was prepared in the dose of 500 mg/kg. Twenty-eight male Wistar rats were assigned to 4 equal sized groups: two control groups and two treated groups which were supplemented with either PS or OMZ orally at a dose of 500 mg/kg and 20 mg/kg body weight respectively. After 28 days of treatment, one control group, the PS and OMZ group were subjected to a single exposure of water-immersion restraint stress for 3.5 h. After the last exposure to stress, the stomach was excised for evaluation of the parameters. Results Oral supplementation of PS was as effective in preventing the formation of gastric lesion when compared with OMZ (p < 0.05). The increased gastric acidity and MDA due to stress was also reduced with supplementation of PS and OMZ. Only PS had the ability to reduce prostaglandin E2 loss (p = 0.0067) and have the ability to down regulate cyclooxygenase-2 (COX-2) mRNA expression (p = 0.01) with stress exposure. Conclusions Piper sarmentosum possesses a similar protective effect against stress-induced gastric lesions as omeprazole. The protective effect was associated with decreased lipid peroxidation, increased prostaglandin E2, reduction in gastric acidity and reduction in COX-2 mRNA expression which was altered by stress.

Enteral supplementation of palm vitamin e and alpha-tocopherol: Pre-clinical aspects

Amniotic fluid is the enteral “diet” of the developing fetus, while the first mammary gland secretion, colostrum, is the natural diet of the newborn mammal. Both diets contain nutrients but also growth factors, immune-modulating components, and antibacterial agents that support perinatal organ development, particularly of the gastrointestinal (GI) tract. Birth requires a sudden transition to nutrient uptake via the GI tract and exposure to microorganisms. Ingestion of amniotic fluid before birth and of colostrum just after birth helps to adapt GI functions and provides protection against detrimental immune responses. Experimental studies indicate that these fluids may also have beneficial effects in certain GI disease conditions, particularly those related to immature digestive and immune function. We provide a brief review of the functions and composition of mammalian amniotic fluid and colostrum, and we describe how these fluids may have a therapeutic potential for GI conditions in some pediatric patients, particularly preterm infants. The composition of the two fluids varies widely among different species and the effects are likely highly species specific. Some effects may however be species independent, maybe allowing colostrum from one species (i.e., lactating cows) to be used as the first enteral diet for infants for whom mother’s milk is lacking. The use of amniotic fluid and bovine colostrum in the critical care of neonates is still at an experimental stage, but animal studies have shown promising results. List of Abbreviations GI Gastrointestinal MEN Minimal enteral nutrition NEC Necrotizing enterocolitis SBS Short bowel syndrome