Effect of diesel exhaust particles on renal vascular responses in rats with chronic kidney disease.

Several recent studies have indicated the possible association between exposure to particulate air pollution and the increased rate of morbidity and mortality in patients with kidney diseases. The link of this observation to vascular damage has not been adequately addressed. Therefore, this study aims to investigate possible vascular damage that might be associated with exposure to diesel exhaust particles (DP) in adenine (AD)-induced chronic kidney disease (CKD) in rats, and the possible ameliorative effect of gum acacia (GA). CKD was induced by feeding AD (0.75%, w/w), and DP (0.5 mg/kg) was instilled intratracheally every second day and GA was given concomitantly in the drinking water at a dose of 15% w/v. All treatments were given concomitantly for 28 days. Changes in renal blood flow (RBF) and systolic and diastolic blood pressure were monitored in these animals after anesthesia, together with several other endpoints. Exposure to DP significantly reduced RBF and this was significantly potentiated in AD-treated rats. Phenylephrine-induced decreases in RBF and increases in systolic and diastolic blood pressure were severely potentiated in rats exposed to DP, and these actions were significantly augmented in AD-treated rats. GA did not significantly affect the vascular impairment induced by AD and DP given together. This study provides experimental evidence that exposure to particulate air pollution can exacerbate the vascular damage seen in patients with CKD. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 541-549, 2017.

Gum acacia mitigates genetic damage in adenine-induced chronic renal failure in rats.

BACKGROUND: Subjects with chronic renal failure (CRF) exhibit oxidative genome damage, which may predispose to carcinogenesis, and Gum acacia (GumA) ameliorates this condition in humans and animals. We evaluated here renal DNA damage and urinary excretion of four nucleic acid oxidation adducts namely 8-oxoguanine (8-oxoGua), 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), 8-oxoguanosine (8-oxoGuo) and 8-hydroxy-2-deoxyguanisone (8-OHdg) in rats with adenine (ADE)-induced CRF with and without GumA treatment. MATERIALS AND METHODS: Twenty-four rats were divided into four equal groups and treated for 4 weeks. The first group was given normal food and water (control). The second group was given normal food and GumA (15% w/v) in drinking water. The third group was fed powder diet containing adenine (ADE) (0·75% w/w in feed). The fourth group was fed like in the third group, plus GumA in drinking water (15%, w/v). RESULTS: ADE feeding induced CRF (as measured by several physiological, biochemical and histological indices) and also caused a significant genetic damage and significant decreases in urinary 8-oxo Gua and 8-oxoGuo, but not in the other nucleic acids. However, concomitant GumA treatment reduced the level of genetic damage in kidney cells as detected by Comet assay and significantly reversed the effect of adenine on urinary 8-oxoGuo. CONCLUSIONS: Treatment with GumA is able to mitigate genetic damage in renal tissues of rats with ADE-induced CRF.

The Salutary Effects of Diminazene, Lisinopril or Valsartan on Cisplatin - Induced Acute Kidney Injury in Rats: A Comparative Study.

Nephrotoxicity as a cause of acute kidney injury (AKI) induced by cisplatin (CP), limits its usefulness as an anticancer agent. Diminazene, an angiotensin converting enzyme 2 activator, exhibited renoprotective properties on rat models of kidney diseases. This research aims to investigate the salutary effect of diminazene in comparison with lisinopril or valsartan in CP-induced AKI. The first and second groups of rats received oral vehicle (distilled water) for 9 days, and saline injection or intraperitoneal CP (6 mg/kg) on day 6, respectively. Third, fourth, and fifth groups received intraperitoneal injections of CP on day 6 and diminazene (15 mg/kg/day, orally), lisinopril (10 mg/kg/day, orally), or valsartan (30 mg/kg/day, orally), for 9 days, respectively. 24h after the last day of treatment, blood and kidneys were removed under anesthesia for biochemical and histopathological examination. Urine during the last 24 h before sacrificing the rats was also collected. CP significantly increased plasma urea, creatinine, neutrophil gelatinase-associated lipocalin, calcium, phosphorus, and uric acid. It also increased urinary albumin/creatinine ratio, N-Acetyl-beta-D-Glucosaminidase/creatinine ratio, and reduced creatinine clearance, as well the plasma concentrations of inflammatory cytokines [plasma tumor necrosis factor-alpha, and interleukin-1beta], and significantly reduced antioxidant indices [catalase, glutathione reductase , and superoxide dismutase]. Histopathologically, CP treatment caused necrosis of renal tubules, tubular casts, shrunken glomeruli, and increased renal fibrosis. Diminazine, lisinopril, and valsartan ameliorated CP-induced biochemical and histopathological changes to a similar extent. The salutary effect of the three drugs used is, at least partially, due to their anti-inflammatory and antioxidant effects. Keywords: Cisplatin, Diminazene, ACE2 activator, Lisinopril, Valsartan, Acute kidney injury.

Ellagic acid protects against cisplatin-induced nephrotoxicity in rats: a dose-dependent study.

BACKGROUND: The anticancerdrug cisplatin (CP) causes nephrotoxicity through different mechanisms, including generation of free radicals. Ellagic acid (EA) is a polyphenolic antioxidant found in fruits and nuts. AIM: This study aimed to investigate the ability of different doses of EA to ameliorate CP nephrotoxicity in rats. MATERIALS AND METHODS: Animals were randomly divided into six groups and treated with saline; CP alone (6 mg/kg); two doses of EA, both alone (10 and 30 mg/kg) or with CP. RESULTS: Treatment with CP alone reduced body weight, water intake, urine output, and renal total antioxidant and reduced glutathione (GSH) concentrations (p < 0.01). In addition, it increased relative kidney weight, plasma creatinine, and blood urea nitrogen (BUN) concentrations (p < 0.01). However, a dose of 30 mg/kg EA mitigated most of the CP-induced actions, but no effect was seen for the 10 mg/kg dose. Histopathologically, rats given CP+EA30 showed < 25% necrotic lesions in the renal cortical area compared with > 60% in rats treated with CP alone. Molecular analysis showed that clusterin (Clu) mRNA and protein were expressed in all treated groups, meanwhile kidney injury molecule-1 (Kim-1) mRNA and protein were only expressed in the CP and CP+EA treated rats. CONCLUSIONS: EA (30 mg/kg) ameliorated most of the physiological, histological, and biochemical markers of CP nephrotoxicity. The molecular findings in this work did not completely tally with the conventional method used. The overexpression of the molecular markers may be related to the EA induced repair mechanism.

Waterpipe smoke inhalation induces lung injury and aortic endothelial dysfunction in mice.

Waterpipe tobacco smoking (WPS) inhalation has been shown to trigger endothelial dysfunction and atherosclerosis. However, the mechanisms underlying these effects are still unknown. Here, we assessed the impact and underlying mechanism of WPS exposure for one month on endothelial dysfunction using aortic tissue of mice. The duration of the session was 30 min/day and 5 days/week. Control mice were exposed to air. Inhalation of WPS induced an increase in the number of macrophages and neutrophils and the concentrations of protein, tumor necrosis factor alpha (TNF alpha), interleukin (IL)-1beta, and glutathione in bronchoalveolar lavage fluid. Moreover, the concentrations of proinflammatory cytokines (TNF alpha, IL-6 and IL-1beta), adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin and P-selectin) and markers of oxidative stress (lipid peroxidation, glutathione, superoxide dismutase and nitric oxide) in aortic homogenates of mice exposed to WPS were significantly augmented compared with air exposed mice. Likewise, the concentration of galectin-3 was significantly increased in the aortic homogenates of mice exposed to WPS compared with control group. WPS inhalation induced vascular DNA damage assessed by comet assay and apoptosis characterized by a significant increase in cleaved caspase-3. While the aortic expression of phosphorylated nuclear factor kappaB (NF-kappaB) was significantly increased following WPS inhalation, the concentration of sirtuin 1 (SIRT1) was significantly decreased in WPS group compared with air-exposed group. In conclusion, our study provided evidence that WPS inhalation triggers lung injury and endothelial inflammation, oxidative stress and apoptosis which were associated with nuclear factor-kappaB activation and SIRT1 down-regulation.

Osteoradionecrosis of the lamina papyracea leading to recurrent orbital infections-A case study.

Osteoradionecrosis (ORN) is a well-known complication of radiotherapy (RT) to the sino-nasal cavity and nasopharynx. Here, we report a case of recurrent orbital infections secondary to ORN of the lamina papyracea (LP). A 66-year-old female presented to our unit with right periorbital swelling and pain after having undergone chemotherapy and proton beam irradiation to her ethmoid sinuses for sino-nasal undifferentiated carcinoma (SNUC) 5 years prior. She had also undergone endoscopic sinus surgery for chronic rhinosinusitis about a year prior to the current presentation. Her post-operative course was notable for recurrent episodes of pre-septal cellulitis occurring about 3 months apart that were increasingly severe. Examination revealed right proptosis, and endoscopy showed an exposed and denuded LP with scant crusting of the ethmoid sinuses. Microbial studies did not yield any significant growth, and imaging showed enhancement of the right orbit. The working diagnosis was acute right orbital cellulitis secondary to ORN of the right LP. She was treated with broad spectrum intravenous antibiotics and systemic steroids, but experienced minimal symptomatic improvement. She then underwent endoscopic resection of the right LP, and histopathological examination showed osteonecrosis on an inflammatory background. Post-operatively, all orbital symptoms resolved and she was well at 6 months' follow up. In the discussion, we highlight additional factors in our patient that may have contributed to this clinical presentation, and hope that this report raises awareness of a rare complication of RT to the sino-nasal cavity.

Insulin resistance in nondiabetic Egyptian patients with chronic hepatitis C virus. / Resistencia a la insulina en pacientes egipcios no diabéticos infectados con el virus de hepatitis C crónica.

INTRODUCTION AND OBJECTIVE: Insulin resistance and diabetes mellitus are frequently associated with chronic hepatitis C virus (HCV) infection, and it is thought that the presence of insulin resistance aggravates liver disease. We aimed to evaluate insulin resistance in nondiabetic Egyptian patients with chronic HCV infection. MATERIALS AND METHODS: Sixty nondiabetic patients with chronic HCV infection and 30 healthy nondiabetic non-HCV-infected volunteers were enrolled in our study. They were divided into 3 groups: group 1 included 30 patients with chronic HCV infection with no cirrhosis, group 2 included 30 patients with chronic HCV infection and cirrhosis of the liver, and group 3 included 30 healthy volunteers as controls. The entire study population underwent a detailed clinical history and physical examination, weight and height measurement, routine laboratory tests, and viral marker determination that included hepatitis B surface antigen and HCV antibodies. PCR analysis was carried out on the patients with positive HCV antibodies. Fasting blood sugar and fasting insulin levels were measured in all the patients, and insulin resistance was calculated according to the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Patients with cirrhosis of the liver (2 patients with Child class A, 12 patients with Child class B, and 16 patients with Child class C) showed higher insulin resistance levels (2.76±0.97) than the patients with chronic HCV infection and no cirrhosis (2.03±0.743) and the control group (1.22±0.38). The p value was significantly different between the 3 groups. There were direct and significant correlations between insulin resistance, fasting blood sugar, and fasting insulin levels. Patients with chronic HCV infection showed significantly higher fasting insulin and glucose levels than the control group. CONCLUSION: Chronic HCV-infected patients showed significantly higher insulin resistance levels than the normal population, even in the absence of hepatic dysfunction and cirrhosis.

Ameliorative effect of sesamin in cisplatin-induced nephrotoxicity in rats by suppressing inflammation, oxidative/nitrosative stress, and cellular damage.

Nephrotoxicity of cisplatin (CP) involves renal oxidative stress and inflammation, and sesamin (a major liganin in many plants) has strong antioxidant and antiinflammatory actions. Therefore, we investigated here the possible mitigative action of sesamin on CP nephrotoxicity in rats. Sesamin was given orally (5 mg/kg/day, 10 days), and on the 7th day, some of the treated rats were injected intraperitoneally with either saline or CP (5 mg/kg). On the 11th day, rats were sacrificed, and blood and urine samples and kidneys were collected for biochemical estimation of several traditional and novel indices of renal damage in plasma and urine, several oxidative and nitrosative indices in kidneys, and assessment of histopathological renal damage. CP significantly and adversely altered all the physiological, biochemical and histopathological indices of renal function measured. Kidneys of CP-treated rats had a moderate degree of necrosis. This was markedly lessened when CP was given simultaneously with sesamin. Sesamin treatment did not significantly alter the renal CP concentration. The results suggested that sesamin had ameliorated CP nephrotoxicity in rats by reversing the CP-induced oxidative stress and inflammation. Pending further pharmacological and toxicological studies sesamin may be considered a potentially useful nephroprotective agent.

Comparative protective effect of N-acetyl cysteine and tetramethylpyrazine in rats with gentamicin nephrotoxicity.

Gentamicin (GM) is used against serious and life-threatening infections, but its use is limited by the occurrence of nephrotoxicity, which involves the generation of free radicals. In this work we tested the effect of a compound with antioxidant properties, tertamethylpyrazine (TMP), a major constituent of the Chinese medicinal plant Lingusticum wallichi, on GM-induced nephrotoxicity, and compared it with an established anti-oxidant compound N-acetyl cysteine (NAC). Six groups of rats were studied: (1) control, treated orally (p.o.) and intraperitoneally (i.p.) with saline; (2) treated i.p. with GM (80 mg kg(-1) per day for 6 days); (3) TMP, given p.o. (100 mg kg(-1) per day for 10 days) + GM (same dose as above during the last 6 days); (4) NAC, given i.p. (500 mg kg(-1) per day for 10 days) + GM as above; (5) TMP (100 mg kg(-1) per day for 10 days) + saline; (6) NAC (500 mg kg(-1) per day for 10 days) + saline. GM nephrotoxicity was characterized by reduced creatinine clearance, increased creatinine and urea concentrations in plasma, increased urinary excretion of N-acetyl-beta-d-glucosaminidase (NAG) and total protein. These functional and structural alterations were prevented or ameliorated by NAC treatment, while TMP had only a slight mitigating effect that was less marked than that produced by NAC. The concentration of GM in the renal cortex of the rats given GM + NAC (but not TMP) was lower than that found in rats treated with GM alone by about 25%. The mechanism by which NAC and, to a lesser extent TMP, protected against GM-induced nephrotoxicity may be related, at least in part, to the decrease in oxidative stress in renal cortex.

Amelioration of cisplatin-induced nephrotoxicity in rats by tetramethylpyrazine, a major constituent of the Chinese herb Ligusticum wallichi.

Nephrotoxicity of the anticancer drug, cisplatin (CP) involves enhanced renal generation of reactive oxygen metabolites and lipid peroxidation caused by decreased levels of antioxidants and antioxidant enzymes. Tetramethylpyrazine (TMP) is known to act as a strong antioxidant. Therefore, in the present work, we aimed at testing the possible protective or palliative effect of TMP on CP nephrotoxicity in rats. TMP was given orally at a dose of 80 mg . kg(- 1) . day(- 1) for 7 days. Some of these rats were given a single intraperitoneal injection of CP (or vehicle) at a dose of 6 mg/kg on Day 6 of treatment. Animals were sacrificed 6 days after CP (or vehicle) treatment, and blood, urine, and kidneys were obtained. Nephrotoxicity was assessed biochemically by measuring creatinine and urea in serum, reduced glutathione (GSH) concentration in renal cortex, by urinalysis, and histopathologically by light microscopy. CP significantly increased the concentration of urea and creatinine (P < 0.05) by about 128% and 170%, respectively; increased urine volume and N-acetyl-beta-D-glucosaminidase (NAG) activity; and significantly decreased osmolality and protein concentrations. CP treatment reduced GSH by about 34% (P < 0.05) and superoxide dismutase (SOD) and total antioxidant activity (TOX) by about 28% and 21%, respectively (P < 0.05). TMP pretreatment significantly mitigated all of these effects. Sections from saline- and TMP-treated rats showed apparently normal proximal tubules. However, kidneys of CP-treated rats had a moderate degree of necrosis. This was markedly reduced when CP was given after pretreatment with TMP. CP cortical concentration was not significantly altered by TMP treatment. The results suggest that TMP ameliorated the histological, physiological, and biochemical indices of nephrotoxicity in rats. Pending further pharmacological and toxicological studies, TMP may potentially be useful as a nephroprotective agent.

Ontogenic aspects of cisplatin-induced nephrotoxicity in rats.

A multi-age rat model was evaluated to identify a potential age-related difference in kidney injury following administration of cisplatin (CP). Different age groups of Wistar rats (aged 3, 7, 11 and 24 weeks) were given CP intraperitoneally (6 mg/kg) and sacrificed 6 days thereafter. CP-induced nephrotoxicity caused significant decreases in body weight, creatinine clearance, urine osmolality, plasma total anti-oxidant status, cortical glutathione (GSH) concentration and superoxide dismutase activity. It increased kidney weight and plasma concentrations of creatinine and urea. It increased urinary N-acetyl-beta-D-glucosaminidase activity and protein concentration. Most of the above actions were more marked as the animals advanced in age, except for the changes in GSH, which were similar in all age groups. CP produced necrosis in renal tubules and epithelial vacuolization, the extent of which was more evident as the rats grew older. Renal CP concentration was increased with the increased age of the animal, and the cortical CP concentration in 3 week-old rats was nearly half that of 24 week-old rats. This study showed that the vulnerability profile of each age group was different, suggesting that a multi-age pediatric/geriatric animal model is appropriate to assess, more completely, age-dependent changes in drug toxicity.

The ameliorative effect of cysteine prodrug L-2-oxothiazolidine-4-carboxylic acid on cisplatin-induced nephrotoxicity in rats.

Pathogenesis of nephrotoxicity of the synthetic anticancer drug cisplatin (CP) involves generation of reactive oxygen species and free radicals in the kidney cortex, and cysteine prodrug l-2-oxothiazolidine-4-carboxylic acid (OTC) has been confirmed to have a strong antioxidant action. Therefore, in the present work, we aimed at testing the possible protective or palliative effect of OTC on CP nephrotoxicity in rats. OTC was given at an oral dose of 150 mg/kg/day for 7 days. On day 7, some of these rats were given a single intraperitoneal injection of CP (or vehicle) at a dose of 6 mg/kg. Rats were killed, blood and urine samples were collected, and the kidneys were removed 6 days after CP treatment. Nephrotoxicity was evaluated histopathologically by light microscopy, and biochemically by measuring the concentrations of creatinine and urea in serum, reduced glutathione (GSH) concentration and superoxide dismutase (SOD) activity in renal cortex, and by urinalyses. CP significantly increased the concentrations of urea and creatinine (P < 0.05) by about 128% and 170% respectively. CP treatment reduced cortical GSH concentration by about 34% (P < 0.05), and the activity of SOD by about 28% (P < 0.05). CP treatment significantly increased urine volume and N-acetyl-beta-D-glucosaminidase (NAG) activity, and significantly decreased osmolality and protein concentrations. OTC significantly mitigated all these effects. Sections from saline- and OTC-treated rats showed apparently normal proximal tubules. However, kidneys of CP-treated rats had a moderate degree of necrosis. This appeared to be lessened when CP was given simultaneously with OTC. The concentration of CP in the cortical tissues was not significantly altered by OTC treatment. The results suggested that OTC had ameliorated the histopathological and biochemical indices of nephrotoxicity in rats. Pending further pharmacological and toxicological studies, OTC may potentially be useful as a nephroprotective agent.

The in vivo effects of adenine-induced chronic kidney disease on some renal and hepatic function and CYP450 metabolizing enzymes.

Adenine-induced model of chronic kidney disease (CKD) is a widely used model especially in studies testing novel nephroprotective agents. We investigated the effects of adenine-induced CKD in rats on the activities of some xenobiotic metabolizing enzymes in liver and kidneys, and on some in vivo indicators of drug metabolism (viz pentobarbitone sleeping time, and plasma concentration of theophylline 90 min post administration). CKD was induced by orally feeding adenine (0.25 % w/w) for 35 days. Adenine induced all the characteristics of CKD, which was confirmed by biochemical and histological findings. Glutathione concentration and activities of some enzymes involved in its metabolism were reduced in kidneys and livers of rats with CKD. Renal CYP450 1A1 activity was significantly inhibited by adenine, but other measured isoenzymes (1A2, 3A4 and 2E1) were not significantly affected. Adenine significantly prolonged pentobarbitone-sleeping time and increased plasma theophylline concentration 90 min post administration. Adenine also induced a moderate degree of hepatic damages as indicated histologically and by significant elevations in some plasma enzymes. The results suggest that adenine-induced CKD is associated with significant in vivo inhibitory activities on some drug-metabolizing enzymes, with most of the effect on the kidneys rather than the liver.

Stress associated with road transportation in desert sheep and goats, and the effect of pretreatment with xylazine or sodium betaine.

The present work investigates some clinical, endocrinological, biochemical and haematological variables in desert sheep and goats stressed in the course of individual road transportation, and the influence thereon of pretreatment with an established anti-stressor drug, xylazine HCl, and a test compound, sodium betaine (trimethylglycine). Road transportation for 2h resulted in variable and statistically insignificant increases in heart, pulse and respiratory rates in both control and experimental animals. Transportation stress significantly increased the concentrations of plasma cortisol, and glucose, and decreased that of magnesium. The endogenous thiocyanate concentration was unaffected. The stress also insignificantly decreased the haematocrit (PCV), and the number of lymphocytes, and increased the concentration of haemoglobin. Pretreatment of sheep and goats with xylazine at a single dose of 0.01 mg/kg by the intravenous route significantly ameliorated the effects induced by the stressful stimulus. The effects of pretreatment of the two species with sodium betaine (10 mg/kg) produced variable and insignificant effects.

Antioxidant levels in tissues of young and adult camels (Camelus dromedarius).

In this study, we measured the concentration of some antioxidant substances in erythrocytes hemolysate, liver, kidney and brain in young and adult camels. It has been found that the activity of the antioxidant enzymes glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD) and the concentration of glutathione, ascorbic acid and alpha-tocopherol are high in both young and adult camels. GSH-Px and CAT activities were higher in adult camels than in the young whereas no significant difference in the activity of SOD between young and adult camels was noticed. Glutathione was present in all tissues studied. Ascorbic acid was found to have significantly higher values in young camels. From this study it could be concluded that, as in other mammals, camel tissues contain a powerful antioxidant system. The liver has the highest contents of antioxidants and antioxidant enzymes indicating that it plays an important role in pro-oxidants detoxification. Age has a variable effect on the antioxidant system in camels.

Curcumin has a palliative action on gentamicin-induced nephrotoxicity in rats.

Generation of free radicals in kidney cortex plays an important role in the pathogenesis of gentamicin (GM) nephrotoxicity, and curcumin, the yellow curry pigment isolated from turmeric, has been confirmed to have a strong antioxidant action. Therefore, in the present work, we aimed at testing the possible protective or palliative effect of curcumin on GM nephrotoxicity. Curcumin was given to rats at an oral dose of 200 mg/kg/day for 10 days, and in some of these rats GM was also injected intramuscularly at a dose of 80 mg/kg/day during the last 6 days of the treatment. Nephrotoxicity was evaluated histopathologically by light microscopy, and biochemically by measuring the concentrations of creatinine and urea in serum, and reduced glutathione (GSH) concentration and superoxide dismutase (SOD) activity in renal cortex. The concentration of GM in renal cortex was measured microbiologically. GM significantly increased the concentrations of urea and creatinine (P < 0.05) by about 111 and 97%, respectively. GM treatment reduced cortical GSH concentration by about 31% (P < 0.05), and the activity of SOD by about 27% (P < 0.05). Curcumin significantly mitigated these effects. Sections from saline and curcumin-treated rats showed apparently normal proximal tubules. However, kidneys of GM-treated rats had a moderate degree of necrosis. The degree of necrosis appeared lessened when GM was given simultaneously with curcumin. The concentration of GM in the renal cortex of the rats given GM + curcumin was significantly (P < 0.05) lower than that found in rats treated with GM alone by about 39%. The results suggested that curcumin had ameliorated the histopathological and biochemical indices of nephrotoxicity in rats. Pending further studies, curcumin may potentially be useful as a nephroprotectant agent.

The ameliorative effect of dates (Phoenix dactylifera L.) on ethanol-induced gastric ulcer in rats.

The present work aimed at testing, in a rat model of ethanol-induced gastric ulceration, a local folk medicinal claim that dates are beneficial in gastric ulcers in humans. Aqueous and ethanolic undialyzed and dialyzed extracts from date fruit and pits were given orally to rats at a dose of 4 ml/kg for 14 consecutive days. On the last day of treatment, rats were fasted for 24 h, and were then given ethanol, 80% (1 ml/rat) by gastric intubation to induce gastric ulcer. Rats were killed after 1 h of ethanol exposure, and the incidence and severity of the ulceration were estimated, as well as the concentrations of gastrin in plasma, and histamine and mucus in the gastric mucosa. A single group of rats that were fasted for 24 h, was administered orally with lansoprazole (30 mg/kg), and was given 80% ethanol as above, 8 h thereafter, served as a positive control. The results indicated that the aqueous and ethanolic extracts of the date fruit and, to a lesser extent, date pits, were effective in ameliorating the severity of gastric ulceration and mitigating the ethanol-induced increase in histamine and gastrin concentrations, and the decrease in mucin gastric levels. The ethanolic undialyzed extract was more effective than the rest of the other extracts used. It is postulated that the basis of the gastroprotective action of date extracts may be multi-factorial, and may include an anti-oxidant action.

Isolation stress in desert sheep and goats and the influence of pretreatment with xylazine or sodium betaine.

We studied some behavioural, clinical, biochemical and haematological variables in Desert (Najdi) sheep and goats subjected to the acute stressful stimulus of isolation from the flock, and the influence of pretreatment with xylazine (n = 6) or sodium betaine (n = 6). The isolation stress resulted in increased vocalization and in variable and statistically nonsignificant increases in heart, pulse and respiratory rates. Isolation caused significant increases in the plasma concentrations of cortisol (from about 35.2 to about 83.8 mmol/L) and glucose (from 3.1 to 4.2 mmol/L), and a decrease in that of magnesium (from 0.82 to 0.65 mmol/L). The endogenous thiocyanate concentration was unaffected. The isolation stress also significantly decreased the haematocrit (PCV), and the number of lymphocytes, and increased the concentration of haemoglobin. Pretreatment of sheep and goats with xylazine at a dose of 0.01 mg/kg by the intravenous route significantly ameliorated the effects induced by the stressful stimulus. The effects of pretreatment of the two species with sodium betaine (10 mg/kg) produced variable and nonsignificant effects. There were no significant differences between sheep and goats in the responses to the isolation stress, except in vocalization, which was greater in sheep than in goats.

High-mobility group box-1 protein in adenine-induced chronic renal failure and the influence of gum arabic thereon.

Pathogenesis of adenine-induced chronic renal failure may involve inflammatory, immunological and/or oxidant mechanisms. Gum arabic (GA) is a complex polysaccharide that acts as an anti-oxidant which can modulate inflammatory and/or immunological processes. Therefore, we tested here the effect of GA treatment (15 % in the drinking water for 4 weeks) in plasma and urine of rats, on a novel cytokine that has been shown to be pro-inflammatory, viz, DNA-binding high-mobility group box-1 protein (HMGB1). Adenine (0.75 % in the feed, 4 weeks) significantly increased indoxyl sulphate, urea and creatinine concentrations in plasma, and significantly decreased the creatinine clearance. GA significantly abated these effects. The concentrations of HMGB1 in urine before the start of the experiment were similar in all four groups. However, 24 h after the last treatment, adenine treatment increased significantly the concentration of HMGB1 when compared with the control. GA treatment did not affect the HMGB1 concentration in urine. Moreover, the concentration of HMGB1 in plasma obtained 24 h after the last treatment in rats treated with adenine was drastically reduced compared with the control group. This may explain its significant rise in urine. In conclusion, HMGB1 can be considered a potentially useful biomarker in adenine induced CRF and its treatment.

Influence of treatment with gum acacia on renal vascular responses in a rat model of chronic kidney disease.

OBJECTIVE: This study was conducted in order to investigate the effects of adenine-induced chronic kidney disease (CKD) on renal blood flow and biochemical changes in rats, and to assess the effect of treatment with gum acacia (GA) thereon. MATERIALS AND METHODS: CKD was induced by feeding rats with adenine (0.25% w/w, five weeks). Concomitantly, some of these rats were also given gum acacia (GA) (15% w/v in the drinking water). Before animals were sacrificed, changes in renal blood flow (RBF) were monitored in anaesthetized rat preparations. Several biochemical and histological renal function tests were also conducted. RESULTS: Adenine-induced CKD significantly impaired the vasopressor actions of acetylcholine, sodium nitroprusside and phenylephrine and concomitant treatment with GA abated these responses. Additionally, plasma concentrations of urea, creatinine, uric acid, indoxyl sulfate, nitrite and nitrate and urinary excretion of protein were all significantly increased by adenine. GA significantly mitigated the severity of adenine-induced changes. CONCLUSIONS: Adenine-induced CKD in rats significantly impaired renal vascular responses to acetylcholine, sodium nitroprusside and phenylephrine and this was mitigated by treatment with GA. This provides another experimental evidence for the usefulness of GA in the amelioration of CKD.