Role of 8-isoprostane as an oxidative stress marker in streptozotocin induced diabetic nephropathy in male rats and its correlation with angiotensin II

To evaluate the role of 8-isoprostane as a contributor of diabetic nephropathy [DN], its usefulness as an early marker of oxidative stress, and its correlation with serum and intrarenal angiotensin II [Ang II] production. The study was conducted on 40 age and weight [250-300 g] matched male albino rats. Ten rats were vehicle treated and served as controls, they constituted group I. The remaining 30 rats were made diabetic for 4 weeks by single intravenous streptozotocin [STZ] injection [50 mg/kg]. The diabetic rats were subdivided into 3 groups. Group II: untreated diabetic rats [n=10], group Ill: insulin treated diabetic rats [n=10], they received subcutaneous insulin injections [3 U/rat/day] for 4 weeks. Group IV diabetic rats [n=10], received combined subcutaneous insulin [3 U/rat/day] and intraperitoneal vitamin E [alpha-tocopherol 20 mg/day] for 4 weeks starting from the first day of the experiment. Blood and 24 hours urine samples were collected from all rats at the end of the 1[st], 2[nd], 3[rd] and 4[th] weeks of the study for determination of serum urea, and urinary excretion rates of proteins and 8-isoprostane. At the end of the study period [4 weeks], blood samples were obtained from all rats by cardiac puncture under ether anesthesia. The rats were sacrificed and kidneys were removed for determination of Ang II in kidney tissue homogenates. Final serum glucose, Ang II, and 8-isoprostane were measured. Untreated diabetic rats showed progressive increase in serum urea, proteinuria, and urinary 8-isoprostane excretion rate throughout the whole study, as compared to control ones. Moreover, serum glucose, 8-isoprostane, Ang II, and kidney tissue Ang II were significantly higher in untreated diabetic rats. Insulin treatment significantly reduced the measured parameters in group III rats as compared to group II. A further decrease of the measured parameters was observed after combined insulin and vitamin E treatment in group IV rats. However, the values did not reach basal levels. Increased serum 8-isoprostane and intrarenal Ang II levels as a result of oxidative stress may contribute to the development of DN in hyperglycemic rats. Insulin in combination with vitamin E may exert a more beneficial effect in reducing or retarding the rate of deterioration of diabetic kidney than insulin alone. The advances in the understanding of the 8-isoprostane pathway not only as an early marker of oxidative stress but also as a culprit in the genesis of target organ damage, may lead to novel therapeutic approaches for several diseases resulting from oxidative stress

Relation between apelin-36 and arginine vasopressin in male rats subjected to water deprivation and volume expansion

The closed anatomical localization in supraoptic and paraventricular nuclei and tissue distribution of apelin-36 and arginine vasopressin [AVP] suggest a role for the peptide apelin-36 in body fluid homeostasis and regulation of AVP release. However, conflicting reports make the precise role of apelin-36 remains to be clarified. To investigate the effect of water deprivation and acute volume expansion on plasma and brain tissue levels of apelin-36 and AVP in an attempt to clarify the interaction between the two peptides in control of body fluid homeostasis. The study was conducted on 40 male albino rats divided into 4 groups. Group I: 10 control rats, group II: 10 rats subjected to 24h-water deprivation [WD], group III: 10 rats subjected to 48h-WD and group IV: 10 rats subjected to acute volume expansion 10% of body weight by infusion of isotonic saline over 40 minutes. The following parameters were measured in all rats; plasma and brain tissue apelin -36 and AVP, plasma Na[+] and K[+] concentrations, urinary excretion rates of Na[+] and K[+] and urine flow rate per minute. Hematocrite value and plasma protein concentrations were measured to investigate the state of dehydration and hydration. Water deprivation induced significant decrease in plasma apelin-36 level associated with an increase in its brain tissue contents. This was mirrored by increased plasma AVP level and decreased brain tissue content. The reverse was detected after acute volume expansion. Moreover, increased apelin-36 concentration in plasma after acute VE was associated with diuresis and natriuresis. A significant negative correlation was detected between plasma as well as brain tissue concentrations of both apelin-36 and AVP. Apelin-36 may be implicated in the control of body fluid homeostasis and exerts opposite action to AVP in this regard. Furthermore it may be an inhibitor of AVP and the two peptides may play complementary roles in maintenance of water balance

Prevalence of salmonellae in shepp and its environment with special reference to detection of virulence associated gene using PCR

The present investigation showed that the incidence of salmonellae in sheep and lambs was [4.49%] and [9.18%] respectively. The incidence in sheep differed according to age and health conditions as it was higher in lamb than in adult and in diseased than apparently healthy as it was [12.73%] and [4.65%] in diseased and apparently healthy lambs. Meanwhile, it was [6.67%] and [3.39%] in diseased and apparently healthy adults sheep respectively. The prevalence of salmonellae in slaughtered sheep was [4.44%] and it was higher in intestines [6.67%] than in livers and lymph nodes [3.33%] each. The prevalence of salmonellae in dead lambs was [11.76%] and this incidence was similar in the examined livers, intestines and lymph nodes [11.76%] each. The incidences in feedstuffs, water, soil, waste samples and swabs from workers' hands in environment of living sheep, lambs and dead lambs were [5.71%, 2.86%, 8.57%, 22.22% and 11.11%] respectively. While, the incidences from drain water, swabs from walls and workers' hands in environment of slaughtered sheep were [10%, 12.5% and 6.67%] respectively. The isolated salmonellae were belonged to 7 serovars and S. Typhimurium was most predominant isolate. Also S. Arizonae, S. Cerro, S. Enteritidis, S. Ferruch, S. Montevideo and S. Sandiego were isolated. S. Arizonae, S. Ferruch, S. Montevido, S. Sandiego and S. Typhimurium harboured the virulence associated gene. While, S. Cerro, S. Enteritidis, S. Typhimurium [from slaughtered sheep] didn't harbour this gene. S. Arizonae, S. Cerro, and S. Ferruch yielded [100%] mortality rate in each, followed by S. Sandiego [80%] then S. Typhimurium, S. Typhimurium [from slaughtered sheep] and S. Enteritidis [60%] each, while S. Montevideo yielded lower mortality rate [40%]. It was clear that [95.24%] of the isolates were susceptible to ciprofloxacin and enrofloxacin then, [90.48%], were susceptible to flumequine and [83.33%] were susceptible to amikacin. On the other hand the lower susceptibility incidences were observed to streptomycin [19.05%] and cefadroxil [23.81%]. Enrofloxacin gave the highest inhibitory effect as its MIC was 0.195-312 micro g/ml for sensitive isolates followed by ciprofloxacin and flumequine with MIC: 0.39-3.12 micro g/ml for sensitive isolates while chloramphenical gave the lowest effect on the isolates as its MIC was 3.12-12.5 micro g/ml for sensitive isolates

Contamination of some local fish with usteria monocytogenes and studying its characterization and control [with 7 tables]

A total of 20 L. monocytogenes strains isolated from some local fish from different shops and markets located in 5 towns in Egypt. The total incidence of L. monocytogenes in raw fish was 9.3%, it was predominated in Clarias [4.19%] followed by Saurus [2.79%] then Sardines [2.33%]. They were phenotypic characterized with respect to 8 characters, carbohydrate fermentation profiles showed variation in utilization of dalcite, lactose, maltose, mannitol, starch and xylose while glucose, salicin, sucrose, trehalose and rhaminose yielded positive in all strains. They were tolerant to NaCl at high salt concentrations ranged from 8% to 20%. The growth inhibition of L. monocytogenes in presence of organic acids not occurred within 5 and 10 minutes but occurred after 24 h incubation at 37°C even with different concentrations [0.5, 1, 2 and 5%]. The positive percent of Congo red binding activity and Lecithinase production were 90% and 85% respectively. The drug susceptibility characterization of L. monocytogenes cleared that all isolates were resistant [100%] to colistin Sulphate, enrofloxacin, nalidixic acid and oxolinic acid, but were susceptible to chloramphenicol [100%] followed by erythromycin [80%], amoxycillin [75%] then oxytetracycline [70%]and ciprofloxacin [65%]. Pathogenicity in laboratory animals showed that 20 strains caused keratoconjunctivities in G. pig and only 16 strains killed the mice within 7 days. All strains were haemolytic to RBCs of horse, sheep, G. pig and human and only showed change in haemolysis with addition of D-mannose as follows 85, 75, 50 and 50% in horse, sheep, G. pig and human RBCs respectively. The count of L. monocytogenes inoculated in Sardine was affected by heat treatment where increasing time of exposure and degree of temperature reduced count as 100°C for 20 minutes completely eliminated L. monocytogenes, while at 70°C for 20 minutes only reduced count and having no effect at 50°C even with increasing time. Whereas treatment with organic acids revealed that when the acid concentration increased, the growth rate of L. monocytogenes decreased and the relative inhibition effect was generally lactic> acetic> citric acid, form interest of this work that low concentration of organic acids [0.5%] enhanced growth of L monocytogenes. Application of antimicrobial ice on Sardine not completely eliminated but reduced L. monocytogenes count from 1 X 10[8] to 1.5 X 10[5] and 2 X 10[3] after 60 and 120 minutes exposure respectively

Role of orexin-A in obesity and type 2 diabetes in male patients and its correlation with leptin hormone

To study role of orexin-A in obesity, type 2 diabetes as well as combined obesity and type2 diabetes in male patients and its correlation with leptin hormone. The study was conducted on 30 male patients and 10 healthy age and sex matched control subjects. The patients were divided into 3 groups each of ten as follow: obese normoglycemic, nonobese type 2 diabetic and obese type 2 diabetic patients. All patients and controls were subjected to full history taking and complete clinical examination with determination of BMI. The following parameters were measured: fasting serum levels of glucose, insulin, triglycerides and glycosylated hemoglobin. Serum orexin-A and leptin concentrations were determined. The results of the study revealed that, serum orexin-A was significantly low in all the studied patient groups as compared to control subjects. Significant high serum leptin levels were detected in all patient groups compared to normal ones. An inverse correlation was found between serum orexin-A and BMJ, leptin, glucose and insulin levels. On the other hand, serum leptin was positively correlated with BMI and insulin levels. Orexin-A is implicated in the pathogenesis of both obesity and type 2 diabetes. Leptin may be an important negative regulator of orexin-A

Comparison of PCR amplification of the FIM a gene and cultural method for detction of salmonellae in food and water

Bacteriological examination of local and imported feedstuff samples revealed that 11 out of 600 feedstuff samples harboured salmonellae with un incidence 1.8%. The highest incidence of isolation was in imported bone and meat meal [4%]. A polymerase chain reaction was performed by amplification fim A gene as specific method for detection of salmonella in feed and water. In order to obtain higher specificity, we have selected a series of primers internal to the fim A gene sequence. The concordance percent between conventional cultural method and PCR of feed and water were 96.6% and 100% respectively. This assay enable to detect 10 C.F.U. / 100 ml water and 10 C.F.U. / 25 g feedstuffs and it could detect only Salmonella strains. The detection of all position samples and the failure to amplify the fragment from non Salmonella strains confirm that the fim A gene contain sequences unique to Salmonella genus and demonstrate that this gene is suitable PCR target for detection of Salmonella bacteria. This rapid assay provides a sensitive and specific means of screening drinking water samples as well as feedstuff samples for the presence of Salmonella spp

Effect of intravenous and intracerebroventricular adrenomedullin injections on cardiovascular and some renal functions in rats

To investigate the effect of intravenous and intracerebroventricular adrenomedullin injections on cardiovascular and some renal functions in rats. 30 male rats were used. They were divided into 3 groups each of ten rats: Group I; rats were injected intravenously with human adrenomedullin 1 -52 [1000 P mole/kg], Group II; rats were injected intracerebroventricularly with human adrenomedullin [300 P mole] and Group Ill; rats were subjected to alpha - sympathetic blockade with phentolamine [10 microg/kg] then dealt with as in group II. The following parameters were measured: arterial blood pressure, heart rate, plasma renin activity, plasma and urinary sodium, urine volume per 24 hours and creatinine clearance. Intravenous adrenomedullin produced hypotension concomitant with tachycardia and increased plasma renin activity. Diuresis, natriuresis and increased creatinine clearance were also observed. In contrast, intracerebroventricular adrenomedullin injection resulted in hypertension which was completely abrogated by alpha - sympathetic blockade. Diuresis and tachycardia were also demonstrated after central administration of the peptide. Intravenous adrenomedullin had clear hypotensive. diuretic and natriuretic effects suggesting a role in regulation of cardiorenal homeostasis. On the other hand, intracerebroventricular adrenomedullin had hypertensive effect through alpha - adrenergic stimulation and a diuretic effect suggesting a role in neural integration of afferent information detailing pressure and volume status of the animal or counter balancing the volume unloading actions of the peptide in the periphery