Anti-inflammatory effects of leptin and cholecystokinin on acetic acid-induced colitis in rats: role of capsaicin-sensitive vagal afferent fibers

Leptin and cholecystokinin (CCK) have a synergistic interaction in the suppression of food intake, and afford similar gastroprotective activity. The present study was designed to investigate the putative protective effects of CCK and leptin on acute colonic inflammation. Leptin or CCK-8s was injected to rats intraperitoneally immediately before and 6 h after the induction of colitis with acetic acid. CCK-A receptor antagonist (L-364,718) or CCK-B receptor antagonist (L-365,260) was injected intraperitoneally 15 min before leptin or CCK treatments. In a group of rats, vagal afferent fibers were denervated by topical application of capsaicin on the cervical vagi. Rats were decapitated at 24 h, and the distal 8 cm of the colon were removed for macroscopic scoring, determination of tissue wet weight index (WWI), histologic assessment and tissue myeloperoxidase (MPO) activity. All inflammation parameters were increased by acetic acid-induced colitis compared to control group. Leptin or CCK-8s treatment reduced these parameters in a similar manner, while co-administration of leptin and CCK was found to be more effective in reducing the macroscopic score and WWI. CCK-8s-induced reduction in the score and WWI was prevented by CCK-A, but not by CCK-B receptor antagonist, whereas neither antagonist altered the inhibitory effect of leptin on colitis-induced injury. On the other hand, perivagal capsaicin prevented the protective effects of both CCK-8s and leptin on colitis. Our results indicate that leptin and CCK have anti-inflammatory effects on acetic acid-induced colitis in rats, which appear to be mediated by capsaicin-sensitive vagal afferent fibers involving the reduction in colonic neutrophil infiltration.     

Studies of short-wavelength collective molecular motions in lipid bilayers using high resolution inelastic X-ray scattering

We summarize a series of experimental results made with the newly developed high resolution X-ray scattering (IXS) instrument on two pure lipid bilayers, including dimyristoylphosphatidylcholine (DMPC) and dilauroylphosphatidylcholine (DLPC) in both gel and liquid crystal phases, and lipid bilayers containing cholesterol. By analyzing the IXS data based on the generalized three effective eigenmode model (GTEE), we obtain dispersion relations of the high frequency density oscillations (phonons) of lipid molecules in these bilayers. We then compare the dispersion relations of pure lipid bilayers of different chain lengths among themselves and the dispersion relations of pure lipid bilayers with those of the cholesterol containing bilayers. We also compare our experimental results with collective dynamics data generated by computer molecular dynamics (MD) simulations for dipalmitoylphosphatidylcholine (DPPC) in gel phase and DMPC in liquid crystal phase.     

The effect of Pseudomonas NCIMB 2021 biofilm on AISI 316 stainless steel

A bioreactor system operating in a continuous mode was designed to generate biofilms on polished and as-received surfaces of AISI 316 stainless steel coupons exposed for 36 d to a pure culture of marine Pseudomonas NCIMB 2021. Scanning electron microscopy (SEM) and atomic force microscopy were employed to determine the degree of surface colonisation and to examine corrosion damage of the steel. X-ray photoelectron spectroscopy analysis was carried out to characterise the chemistry of the passive layers on polished steel stored for a period of time, freshly re-polished coupons, and as-received steel. The effect of biofilms on the composition of layers formed on the steel specimens was evaluated. SEM revealed that the surfaces of polished and stored steel appeared to accumulate more biofilm compared to as-received specimens. Micropitting of steel occurred underneath the biofilm, regardless of surface finish. The concentration of elements in the passive layers differed significantly between freshly re-polished and as-received or polished and stored coupons. In the presence of Pseudomonas NCIMB 2021 biofilm, the composition of the passive layer on the as-received steel surface was considerably altered compared to unexposed steel or steel exposed to abiotic medium.     

Determination of microRNAs associated with adverse left ventricular remodeling after myocardial infarction

Molecular and Cellular Biochemistry - Increasing evidence indicates that microRNA (miRNA) regulated mechanisms in myocardial healing and ventricular remodeling following acute myocardial infarction...     

The effect of angiotensin-converting enzyme inhibitors on experimental colitis in rats

The present study was aimed to investigate the effect of ACE inhibition on trinitrobenzene sulphonic acid (TNBS)-induced colonic inflammation in rats by using captopril and lisinopril. In treatment groups, the rats were treated with ACE inhibitors, captopril or lisinopril (0.1 and 1 mg/kg/day; intraperitoneally). The drugs were given 5 min after induction of colitis and the treatment was continued for 3 days. Three days after the induction of colitis, all rats were decapitated. The distal colon was weighed and the mucosal lesions were scored at both macroscopical at microscopic levels. Malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were assessed in tissue samples. Formation of reactive oxygen species in colonic samples was monitored by using chemiluminescence technique. Serum TNF-alphalevel was assessed in trunk blood. Captopril treatment was found to be beneficial in all parameters, except colonic glutathione content. On the other hand, although stimulation of lipid peroxidation and increase in serum TNF-alpha level were successfully prevented by lisinopril, the morphology of the lesions remained unchanged. In conclusion, sulphydryl and non-sulphydryl ACE inhibitors, captopril and lisinopril do not seem to be similarly effective in TNBS-induced colitis model at least at the doses tested in our study.     

A novel thermophilic anaerobic bacteria producing cyclodextrin glycosyltransferase

A novel thermophilic anaerobic, rod-shaped, non-spore forming, gram positive bacterium was isolated from an oil field in Turkey, that produces cyclodextrin glycosyltransferase (CGTase) from starch. According to the some morphological, biochemical and 16S rRNA analysis, the strain belongs to the genus Thermoanaerobacter. The strain mainly utilizes starch and derivatives, glucose and fructose as carbon source between 45 and 75 °C, optimally at 65 °C. Optimum pH for growth is 7.5. 16S RNA studies indicate that the bacterium has a similarity of 98.3% to homoacetogenic Thermoanaerobacter kivui and the main fermentation product is acetic acid as in the case with homoacetogenic bacteria. The main difference between the bacterium and T. kivui concerns the utilization of starch. Based on the phylogenetic and biochemical analysis, it is proposed that the species are a new member of the genus Thermoanaerobacter. The strain has CGTase activity optimum at 80 °C and pH 7.0–8.0.     

Association of male pattern baldness with angiographic coronary artery disease severity and collateral development

Objective

We aimed to investigate whether there is an association between male pattern baldness and angiographic coronary artery disease (CAD) severity and collateral development, which has not been reported previously.

Methods

Coronary arteriograms, CAD risk factors, lipid parameters and presence and severity of baldness in 511 male patients were prospectively evaluated. Baldness was classified into five groups. Severity of CAD was evaluated with the Gensini scoring system and collateral development with Rentrop scores.

Results

Although subjects with a higher Gensini score had more frequent and severe baldness, they were older than the group with lower Gensini scores. Bald patients had a higher Gensini score when compared with their non-bald counterparts. In univariate analysis, age more than 60, body mass index more than 30, smoking and baldness were predictors of high Gensini scores. In multivariate analysis, only age more than 60, body mass index more than 30 and smoking were independent predictors of a high Gensini score. There were no differences in terms of presence and severity of baldness in subjects with and without adequate collateral development.

Conclusions

There was no relation between presence, severity and age of occurrence of male pattern baldness and Gensini and Rentrop scores, which are important measures of presence and severity of CAD.