Antiproliferative and antiapoptotic effect of thymoquinone on cancer cells in vitro.

OBJECTIVES: Nigella sativa oil and thymoquinone were comparatively tested in vitro for their effects on human cancer cell lines (glioma,T98; prostate, LnCaP) as well as mouse embryonic fibroblast cell lines (3T3), and for the induction of apoptosis. METHODS: Individual cell lines were treated with thymoquinone and N. sativa oil for 24 and 48 hr. Survival rate with MTT, apoptosis with flow cytometry and caspase-9 mRNA enzyme levels with RT-PCR were determined in vitro. RESULTS: Application of respective concentrations of N. sativa oil (excluding 100 µg/mL for 48 hr) did not change the number of tested cell lines, however, treatment with thymoquinone reduced the number of all cells significantly. Thymoquinone also exerted its apoptosis inducing effect through the activation of caspase-9. CONCLUSION: Differing with the type of cancer cells, thymoquinone posseses a strong contentration and time dependent survival reducing effect on cancer cells via apoptosis (Fig. 6, Ref. 22). Text in PDF www.elis.sk.

The effect of leptin and resveratrol on JAK/STAT pathways and Sirt-1 gene expression in the renal tissue of ischemia/reperfusion induced rats.

OBJECTIVE: Our study aimed to investigate the possible modifying effects of leptin and combined use of resveratrol on rat renal I/R injury and their relationship on signal pathways and apoptosis-related mechanisms. BACKGROUND: Renal ischemia-reperfusion (I/R) injury is an important cause of acute renal failure. METHODS: Male Sprague Dawley rats were divided into 5 groups: Control, I/R, I/R+leptin, I/R+resveratrol and I/R+leptin+resveratrol. Leptin (10 µg/kg BW) was administered (i.p.) 30 min prior to I/R. Resveratrol was administered by gavage at 20 mg/kg BW per d for 12 d prior to I/R. The left renal artery was exposed to 1 h of ischemia and 1 h of reperfusion. RESULTS: Resveratrol treatment alone increased TNF-α, TNF-α R1, NF-κB, SIRT-1, STAT1 and STAT3 mRNA levels and decreased caspase 3 protein levels. Leptin treatment alone significantly decreased the caspase 3 protein levels. The combined use of resveratrol and leptin significantly increased STAT3, and caspase 3 mRNA levels, and decreased the caspase 3 protein levels. Apoptosis was significantly decreased especially in the leptin and leptin+resveratrol groups. CONCLUSION: The present study suggest that a combined use of resveratrol and leptin has preventive and regulatory effects on renal I/R injury; the mechanism involves decreasing apoptosis, likely by altering the JAK/STAT pathway and SIRT1 expression (Fig. 8, Ref. 24).

Effects of ceranib-2 on cell survival and TNF-alpha in colon cancer cell line.

OBJECTIVE: The aim of this study was to investigate the effects of a novel anti-cancer drug, ceranib-2, which targets the acid ceramidase, in human colon cancer cell line. MATERIALS AND METHODS: The cell lines were treated with 50 µM of ceranib-2. Relative mRNA expression of TNF-alpha, TNF-R1 and ASAH were assessed by quantitative RT-PCR. RESULTS: Ceranib-2 reduced cell viability in a dose-dependent manner and the apoptotic values of cells following treatment with the dose of 50 µM were reduced significantly both at 24 h and 48 h compared to the control cells (p < 0.001). TNF-alpha receptor 1 (TNF-R1) mRNA levels were reduced significantly in the cell lines treated with both 25 µM and 50 µM of ceranib-2 for 24 h compared to the control cells (p < 0.05), whereas the difference between the treatment and the control cell lines diminished at 48 h. The human acid ceramidase gene (ASAH) mRNA levels were significantly higher in the cell lines treated with 50 µM of ceranib-2 for 48 h than in the other cell lines (p < 0.001). CONCLUSION: The study shows that ceranib-2 increased apoptosis by inducing ASAH expression and reduced TNF-R1 expression in human colon cancer cell lines in a dose and time-dependent manner (Fig. 3, Ref. 17).

Leptin receptor (Ob-R) mRNA expression and serum leptin concentration in patients with colorectal and metastatic colorectal cancer.

The objective of the present study was to investigate the effect of leptin on the progression of colorectal carcinoma to metastatic disease by analyzing the serum leptin concentration and Ob-R gene expression in colon cancer tissues. Tissue samples were obtained from 31 patients who underwent surgical resection for colon (18 cases) and metastatic colon (13 cases) cancer. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA) and Ob-R mRNA expression by real-time polymerase chain reaction (RT-PCR) for both groups. ELISA data were analyzed by the Student t-test and RT-PCR data were analyzed by the Mann-Whitney U-test. RT-PCR results demonstrated that mRNA expression of Ob-R in human metastatic colorectal cancer was higher than in local colorectal cancer tissues. On the other hand, mean serum leptin concentration was significantly higher in local colorectal cancer patients compared to patients with metastatic colorectal cancer. The results of the present study suggest a role for leptin in the progression of colon cancer to metastatic disease without weight loss. In other words, significantly increased Ob-R mRNA expression and decreased serum leptin concentration in patients with metastatic colon cancer indicate that sensitization to leptin activity may be a major indicator of metastasis to the colon tissue and the determination of leptin concentration and leptin gene expression may be used to aid the diagnosis.

Leptin receptor (Ob-R) mRNA expression and serum leptin concentration in patients with colorectal and metastatic colorectal cancer

The objective of the present study was to investigate the effect of leptin on the progression of colorectal carcinoma to metastatic disease by analyzing the serum leptin concentration and Ob-R gene expression in colon cancer tissues. Tissue samples were obtained from 31 patients who underwent surgical resection for colon (18 cases) and metastatic colon (13 cases) cancer. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA) and Ob-R mRNA expression by real-time polymerase chain reaction (RT-PCR) for both groups. ELISA data were analyzed by the Student t-test and RT-PCR data were analyzed by the Mann-Whitney U-test. RT-PCR results demonstrated that mRNA expression of Ob-R in human metastatic colorectal cancer was higher than in local colorectal cancer tissues. On the other hand, mean serum leptin concentration was significantly higher in local colorectal cancer patients compared to patients with metastatic colorectal cancer. The results of the present study suggest a role for leptin in the progression of colon cancer to metastatic disease without weight loss. In other words, significantly increased Ob-R mRNA expression and decreased serum leptin concentration in patients with metastatic colon cancer indicate that sensitization to leptin activity may be a major indicator of metastasis to the colon tissue and the determination of leptin concentration and leptin gene expression may be used to aid the diagnosis.

The effects of PDE5 inhibitory drugs on renal ischemia/reperfusion injury in rats.

The aim of the present study was to evaluate the effects of phosphodiesterase type 5 (PDE5) inhibitory drugs, Tadalafil and Sildenafil, on inducible NOS (iNOS), endothelial NOS (eNOS) and p53 genes expressions and apoptosis in ischemia/reperfusion (I/R) induced oxidative injury in rat renal tissue. Eighty Sprague-Dawley rats (300-350 g) were divided into four groups. In ischemia/reperfusion group, rats were subjected to renal ischemia by clamping the left pedicle for 60 min, and then reperfused for 90 min. On the other hand, in other two groups the rats were individually pretreated with Tadalafil and Sildenafil 1 h before the induction of ischemia. Malondialdehyde (MDA) is determined in renal tissue homogenates by high-performance liquid chromatography, the number of apoptotic cell were calculated by TUNEL method and p53 and eNOS expression were detected with immunohistochemistry. On the other hand, myeloperoxidase (MPO) levels were measured by spectrophotometric method and the mRNA level of iNOS in renal tissue was determined by Real-time PCR (RT-PCR). Our results indicate that MDA and MPO levels were increased in the I/R group than those in the control group. Both Tadalafil and Sildenafil treatment decreased the MDA levels in ischemia/reperfusion group, whereas this effect was more potent with Sildenafil. RT-PCR results showed that, iNOS gen expression increased in the I/R group, but decreased in the PDE5 inhibitory drugs treated group. Apoptotic cells, eNOS levels and p53 positive cells were also decreased in PDE5 inhibitory drugs treated group. We suggest that Tadalafil and Sildenafil have beneficial effects against I/R related renal tissue injury and this protective effect is clearer for Sildenafil than Tadalafil.

Positive inotropic, positive chronotropic and coronary vasodilatory effects of rat amylin: mechanisms of amylin-induced positive inotropy.

Even though there are a few studies dealing with the cardiac effects of amylin, the mechanisms of amylin-induced positive inotropy are not known well. Therefore, we investigated the possible signaling pathways underlying the amylin-induced positive inotropy and compared the cardiac effects of rat amylin (rAmylin) and human amylin (hAmylin).Isolated rat hearts were perfused under constant flow condition and rAmylin or hAmylin was infused to the hearts. Coronary perfusion pressure, heart rate, left ventricular developed pressure and the maximum rate of increase of left ventricular pressure (+dP/dtmax) and the maximum rate of pressure decrease of left ventricle (-dP/dtmin) were measured.rAmylin at concentrations of 1, 10 or 100 nM markedly decreased coronary perfusion pressure, but increased heart rate, left ventricular developed pressure, +dP/dtmax and -dP/dtmin. The infusion of H-89 (50 µM), a protein kinase A (PKA) inhibitor did not change the rAmylin (100 nM)-induced positive inotropic effect. Both diltiazem (1 µM), an L-type Ca2+ channel blocker and ryanodine (10 nM), a sarcoplasmic reticulum (SR) Ca2+ release channel opener completely suppressed the rAmylin-induced positive inotropic effect, but staurosporine (100 nM), a potent protein kinase C (PKC) inhibitor suppressed it partially. hAmylin (1, 10 and 100 nM) had no significant effect on coronary perfusion pressure, heart rate and developed pressure, +dP/dtmax and -dP/dtmin.We concluded that rAmylin might have been produced vasodilatory, positive chronotropic and positive inotropic effects on rat hearts. Ca2+ entry via L-type Ca2+ channels, activation of PKC and Ca2+ release from SR through ryanodine-sensitive Ca2+ channels may be involved in this positive inotropic effect. hAmylin may not produce any significant effect on perfusion pressure, heart rate and contractility in isolated, perfused rat hearts.

Protective effects of doxycycline in ischemia/reperfusion injury on kidney.

Renal ischemia and reperfusion injury is the major cause of acute renal failure and may also be involved in the development and progression of some forms of chronic kidney disease. The aim of this study was to evaluate whether doxycycline, a member of the tetracycline family of antibiotics, protects kidney tissue or not. 36 Sprague-Dawley rats (200-250 g) were used. The animals were divided into three groups: control, ischemia/reperfusion and ischemia/reperfusion+doxycycline group. Rats were subjected to renal ischemia by clamping the left pedicle for 1 h, and then reperfused for 1 h. The ischemia/reperfusion+doxycycline group were pretreated intraperitoneally with doxycycline suspension (10 mg/kg) 2 h before the induction of ischemia. Our results indicate that malondialdehyde, matrix-metalloproteinase-2, interleukin-2, interleukin-6, interleukin-10, interleukin 1-beta and tumor necrosis factor-alpha levels were significantly higher in the ischemia/reperfusion group than those in the control group. Doxycycline administration significantly decreased these parameters. Tissue inhibitor of metalloproteinases-1 levels also increased after ischemia/reperfusion and decreased with doxycycline pretreatment, but these changes were not significantly different. Glutathione levels significantly decreased after ischemia/reperfusion injury when compared with the control group and doxycycline pretreatment significantly increased glutathione levels when compared with the ischemia/reperfusion group. Apoptotic cells and p53 positive cells were significantly decreased in doxycycline treated group. These results suggest that doxycycline reduces renal oxidative injury and facilitates repair. Doxycycline may play a role in a renoprotective therapeutic regimen.

Protective effects of doxycycline in ischemia/reperfusion injury on kidney

Renal ischemia and reperfusion injury is the major cause of acute renal failure andmay also be involved in the development and progression of some forms of chronickidney disease. The aim of this study was to evaluate whether doxycycline, a memberof the tetracycline family of antibiotics, protects kidney tissue or not. 36 Sprague-Dawley rats (200-250 g) were used. The animals were divided into three groups: control,ischemia/reperfusion and ischemia/reperfusion+doxycycline group. Rats weresubjected to renal ischemia by clamping the left pedicle for 1 h, and then reperfusedfor 1 h. The ischemia/reperfusion+doxycycline group were pretreated intraperitoneallywith doxycycline suspension (10 mg/kg) 2 h before the induction ofischemia. Our results indicate that malondialdehyde, matrix-metalloproteinase-2,interleukin-2, interleukin-6, interleukin-10, interleukin 1-beta and tumor necrosisfactor-alpha levels were significantly higher in the ischemia/reperfusion group thanthose in the control group. Doxycycline administration significantly decreased theseparameters. Tissue inhibitor of metalloproteinases-1 levels also increased afterischemia/reperfusion and decreased with doxycycline pretreatment, but thesechanges were not significantly different. Glutathione levels significantly decreasedafter ischemia/reperfusion injury when compared with the control group and doxycyclinepretreatment significantly increased glutathione levels when compared withthe ischemia/reperfusion group. Apoptotic cells and p53 positive cells were significantlydecreased in doxycycline treated group. These results suggest that doxycyclinereduces renal oxidative injury and facilitates repair. Doxycycline may play a role in arenoprotective therapeutic regimen(AU)

Epidermal growth factor increases tissue antioxidant enzyme activities in ethanol-induced gastric injury in rat

The aim of the present study is to investigate whether the antioxidant mechanisms are involved in epidermal growth factor (EGF)-mediated protection from ethanol-induced gastric damage. Twenty four female Sprague-Dawley rats were assigned into 3 groups; control (C) group (n=8) was given physiologic saline by gavage; ethanol (E) group (n=8) was given 1 ml of 80% ethanol (v/v) in distilled water by gavage and EGF group (n=8) was given EGF (100 mg/kg-body wt.) intraperitonealy half an hour before the administration of ethanol. The protein carbonyl content was significantly higher in the E group than the C group (p<0.01). On the other hand, EGF decreased the protein carbonyl content in the EGF group (p<0.01). Gastric myeloperoxidase activity increased significantly after the administration of ethanol (p<0.01). The administration of EGF decreased significantly the myeloperoxidase activity (p<0.01). Although ethanol caused a slight decrease in the catalase activity, no statistical significance was observed between groups E and C. The catalase activity increased significantly after EGF treatment (p<0.01). The superoxide dismutase activity decreased significantly in the E group when compared to the C group (p<0.05) while it was found to be increased significantly in the EGF group in comparison with the E group (p<0.01). In summary, the present results indicate that the gastroprotective effect of EGF in the experimental lesions induced by ethanol could be attributed to its property such as to augment the antioxidant enzyme activities (AU)

Se investiga si los mecanismos antioxidantes están implicados en la protección del factor de crecimiento epidérmico (EGF) sobre el daño gástrico inducido por el alcohol. Veinticuatro ratas hembra se dividieron en tres grupos: las del grupo control (C) recibieron solución salina por vía intragástrica; las del grupo etanol (E) recibieron 1 ml de etanol al 80% (v/v) en agua destilada por la misma vía y a las del grupo EGF se les administró i.p. EGF (100 mg/Kg w.w.) media hora antes del etanol. El contenido en grupos carbonil de las proteínas y la actividad mieloperoxidasa gástrica aumentó significativamente en el grupo E, mientras que disminuyó en el grupo EGF. Aunque el etanol provocó una ligera disminución de la actividad catalasa, no hubo diferencias significativas entre los grupos C y E, pero aumentó por la administración de EGF. La actividad superóxido dismutasa disminuyó en el grupo E respecto del grupo C y resultó incrementada en el grupo EGF respecto del grupo E. En suma, los resultados indican que el efecto gastroprotector del EGF en las lesiones experimentales inducidas por el etanol podrían atribuirse a su efecto estimulador sobre la actividad de enzimas antioxidantes (AU)

Epidermal growth factor increases tissue antioxidant enzyme activities in ethanol-induced gastric injury in rat.

The aim of the present study is to investigate whether the antioxidant mechanisms are involved in epidermal growth factor (EGF)-mediated protection from ethanol-induced gastric damage. Twenty four female Sprague-Dawley rats were assigned into 3 groups; control (C) group (n=8) was given physiologic saline by gavage; ethanol (E) group (n=8) was given 1 ml of 80% ethanol (v/v) in distilled water by gavage and EGF group (n=8) was given EGF (100 mg/kg-body wt.) intraperitonealy half an hour before the administration of ethanol. The protein carbonyl content was significantly higher in the E group than the C group (p<0.01). On the other hand, EGF decreased the protein carbonyl content in the EGF group (p<0.01). Gastric myeloperoxidase activity increased significantly after the administration of ethanol (p<0.01). The administration of EGF decreased significantly the myeloperoxidase activity (p<0.01). Although ethanol caused a slight decrease in the catalase activity, no statistical significance was observed between groups E and C. The catalase activity increased significantly after EGF treatment (p<0.01). The superoxide dismutase activity decreased significantly in the E group when compared to the C group (p<0.05) while it was found to be increased significantly in the EGF group in comparison with the E group (p<0.01). In summary, the present results indicate that the gastroprotective effect of EGF in the experimental lesions induced by ethanol could be attributed to its property such as to augment the antioxidant enzyme activities.

Cardioprotection with resveratrol pretreatment: improved beneficial effects over standard treatment in rat hearts after global ischemia.

OBJECTIVE: The major objective of the present study is to evaluate the potential role of resveratrol (RVT), a natural antioxidant found in grapes and red wine, in protecting the myocardium from the deleterious effects of ischemia-reperfusion (I/R) injury using isolated rat hearts. METHODS: Langendorff perfused isolated rat hearts were subjected to 60 min of global ischemia following 60 min of reperfusion. RVT was given according to chronic pretreatment and/or acute treatment protocols. Animals received RVT at the dose of 20 mg/kg via an intragastric tube for 14 days before the experiment and/or at the infusion concentration of 10 microM for 30 min before the onset of ischemia. The myocardial postischemic recovery was compared using hemodynamic data (peak systolic pressure, end diastolic pressure, and +dP/dtmax), coronary flow, biochemical parameters (LDH, CK-MB, cTnI, myoglobin) from coronary effluent, and oxidative stress markers (MDA, GSH, carbonyl) from heart tissue homogenates in each group. RESULTS: RVT pretreatment and treatment protocols have provided increased preservation in myocardial recovery following global ischemia compared to a non-treated group. Furthermore, the ischemic damage of myocardium was significantly lower in chronic pretreated rats than in the acutely treated group. In contrast, no significant difference was observed in cardioprotective effects of RVT between the only pretreated group, and both the pretreated and treated group throughout reperfusion. CONCLUSION: The findings from this study indicate that RVT has potent cardioprotective properties against I/R injury in rat hearts. The study also highlighted that the administration of RVT, as pretreatment, has amplified the beneficial effects over the standard treatment.

Effect of leptin on renal ischemia-reperfusion damage in rats.

Tumor necrosis factor-alpha (TNF-alpha) has been established as an important mediator in renal ischemia-reperfusion (I/R) injury. Leptin, a product of the ob gene, has been known to exhibit cytoprotective effects on renal tissue, but its effect on renal tissue TNF-alpha level after renal I/R injury in rats remains unknown. The purpose of the study was to evaluate the effects of leptin on renal tissue TNF-alpha, malondialdehyde (MDA), protein carbonyls (PCs) and total sulfydryl group (SH) levels, and plasma nitrite levels after renal I/R injury in rats. The animals were divided into three groups: control, I/R and I/R+leptin. Rats were subjected to renal ischemia by clamping the left pedicle for 45 min, and then reperfused for 1 h. The I/R+leptin group was pretreated intraperitoneally with leptin (10 microg/kg) 30 min before the induction of ischemia. Our results indicate that MDA, TNF-alpha levels, and PCs were significantly higher in the I/R group than those in the control group (p < 0.05). The administration of leptin decreased these parameters (p < 0.05) significantly. The SH level was observed to significantly decrease after I/R injury when compared to the control group (p < 0.05). Leptin treatment significantly increased tissue SH and plasma nitrite levels when compared to the I/R group (p < 0.05). Plasma nitrite levels did not change significantly in I/R when compared to the control. These results suggest that leptin could exert a protective effect on I/R induced renal damage by decreasing TNF-alpha levels and increasing nitrite level.

Lidocaine-containing Euro-Collins solution prevents renal injury in the isolated perfused canine kidney exposed to prolonged cold ischemia.

Previous studies have reported a decreased incidence of delayed graft function after cadaveric transplantation with the use of lidocaine pretreatment of the donor. We evaluated the effects of lidocaine on prolonged cold ischemia and reperfusion injury in a canine model of isolated kidney perfusion (IPK). The purpose of this study was to evaluate the renal function of isolated perfused canine kidneys after 48 h of cold storage with Euro-Collins (EC) solution or EC solution plus lidocaine. Isolated perfused canine kidneys were randomized into four groups which contained six kidneys: I) cold flush with EC solution and immediately reperfused, II) cold flush with EC solution plus lidocaine and immediately reperfused, III) 48 h of cold storage with EC and reperfusion, IV) 48 h of cold storage with EC solution plus lidocaine and reperfusion. The measured renal functions were glomerular filtration rate, urine production, perfusate flow, urinary lactic dehydrogenase (ULDH), Na reabsorptive capacity, and tissue MDA levels. Histological examination was performed after reperfusion. The tubular functions of kidneys preserved with EC solution containing lidocaine were better when compared with the kidneys preserved with EC alone. Tubular injury marker levels (ULDH) in group IV were significantly lower than in group III and lidocaine also reduced lipid peroxidation during reperfusion. This is in agreement with the histological results. The results of the present study can be taken as evidence of the cytoprotective effect of lidocaine, which may therefore be accepted as a useful agent for kidney preservation.

Modified method for the determination of capillary electrophoresis nitric oxide-correlated nitrate in tissue homogenates.

A modified capillary electrophoretic method for the determination of nitric oxide correlated nitrate in several tissue homogenates is described in this study. The method was developed using a running buffer consisting of 200 mM lithium chloride and 10 mM borate buffer at pH 8.5, in a fused-silica column total 82 cm, effective 43 cm length and 75 microm I.D. The signal was measured at 214 nm and controlled current of 200 microA (equivalent to 12.7 kV) was applied in the reversed polarity direction. The sample was injected by vacuum pressure 50 ms (25 nl). In these conditions, bromide as internal standard and nitrate appeared at 7.2 and 8.9 min, respectively. Whole validation procedures were applied and satisfactory results were obtained. The nitrate levels of the tissue homogenates of control and L-NAME applied (heart, brain, kidney, stomach, lung, testis and liver) were monitored by the present method and it was decided that the method is precise and accurate.

The effect of stress and in vivo vasoactive intestinal peptide (VIP) treatment on the response of isolated rat aorta to norepinephrine, angiotensin II and vasopressin, and adventitial mast cells.

The effects of cold-restraint stress, repeated over 3 days, and treatment of rats with vasoactive intestinal peptide (VIP) on the contractile responses of isolated aorta to vasoconstrictors, and on aortic adventitial mast cells were investigated. Stress significantly reduced the contractile response of rat aorta smooth muscle to norepinephrine (NE), angiotensin II (Ang II) and vasopressin (VP). Decreased sensitivity to NE, Ang II and VP may result from decreased receptor density, and affinity or reduced effector efficacy. Stress induced degranulation, decreased the number and changed the granular content of mast cells; all degranulated mast cells were stained with alcian blue, and the percentage of safranin staining cells was decreased. Given prior to stress, VIP reversed the reduced contractile responses and sensitivity of aorta to NE and Ang II but had no effect on VP subsensitivity. VIP also inhibited stress-induced degranulation of mast cells, and after VIP only alcian blue-stained mast cells were seen. When VIP was given to non-stressed rats, the contractile response of the aorta to NE, but not Ang II or VP, was increased compared with control. Mast cell count was decreased in the adventitia of non-stressed VIP treated rats. The results indicate that stress decreases the heparin content of mast cells and VIP has an additive effect. In conclusion, VIP modulates both stress-induced mast cell activity and reduced sensitivity of aorta smooth muscle to NE and Ang II. It can be suggested that VIP may moderate some effects of stress on vascular pathophysiology.

The protective effect of vasoactive intestinal peptide (VIP) on stress-induced gastric ulceration in rats.

The pathogenesis of cold-restraint stress ulcer involves various factors and is not completely understood. Mast cell degranulation, increased gastric muscular contractility, diminished mucosal blood flow, release of several biogenic amines, activated polymorphonuclear leukocytes, and lipid peroxidation which results from toxic oxygen molecules were suggested to be related to the production of gastric damage by cold-restraint stress. Recent evidence strongly indicates that VIP has a modulatory effect on tissue injury. Sprague-Dawley rats were used in two series of experiments. One set of rats was exposed to cold-restraint stress with some of the rats pretreated with VIP. The second set of rats was exposed to cold-restraint stress and then was administered VIP for different durations. Cold-restraint stress induced gastric lesions and mast cell degranulation and also increased lipid peroxidation in gastric tissue. VIP prevented stress-induced ulcers and mast cell degranulation and protected gastric tissue from lipid peroxidation. When VIP was used after induction of stress ulcer it was therapeutically beneficial. Thanks to its antioxidant and anti-inflammatory activity, VIP can be valuable in the prevention of gastric mucosal damage induced by cold-restraint stress.