Expression and Characterization of a New Self-Sufficient P450 Monooxygenase (P450 AZC1) from Azorhizobium caulinodans

Oxyfunctionalization of non-activated carbon bonds by P450 monooxygenases have drawn great industrial attraction. Self-sufficient P450s containing catalytic heme and reductase domains in a single polypeptide chain offer many advantages since they do not require external electron transfer partners. Here, we report the first P450 enzyme identified and expressed from Azorhizobium caulinodans. Firstly, expression conditions of P450 AZC1 were optimized for enhanced expression in E.coli. The highest P450 content was obtained in E.coli Rosetta DE3 plysS when it was incubated in TB media supplemented with 0.75 mM IPTG, 0.5 mM ALA, 0.75 mM FeCl3 at 25 °C for 24 hours. Subsequently, the purified enzyme showed broad substrate spectrum including fatty acids, linear and cyclic alkanes, aromatics and pharmaceuticals. Finally, P450 AZC1 showed optimal activity at pH 6.0 and 40 °C and a broad pH and temperature profile, making it a promising candidate for industrial applications.

The effects of dragon fruit (Hylocereus polyrhizus) extract on indomethacin-induced stomach ulcer in rats

The aim of this study was to investigate the effects of red dragon fruit (Hylocereus polyrhizus) extract (DFE) on the stomach in ulcer model induced by indomethacin in rats. Effects of DFE were evaluated in indomethacin-induced gastric damage model on Sprague-Dawley rats. Experimental model: all rats were fasted for 24 h. At the end of this period, DFE was administered to the ulcer-induced groups. One hour after this application, a dose of 25 mg/kg of indomethacin was applied by oral gavage to all groups except the HEALTHY and DFE1000 groups. Six hours after indomethacin administration, the rats were euthanized with high-dose anesthesia and the experiment was terminated. Macroscopic and microscopic analyses for investigating ulcerative area, molecular and biochemical analyses for oxidative damages investigation and molecular analyses for the effect mechanism of indomethacin and DFE were conducted on stomach tissues in the study. While oxidative stress-associated markers such as MDA, BAX, and Caspase 3 increased dramatically in the indomethacin group, GSH antioxidant levels decreased. It was observed that these parameters were significantly improved in DFE 500 mg/kg and DFE 1000 mg/kg groups compared to ulcer group, and the results of especially DFE 1000 mg/kg group were similar to famotidine group. We observed that our histopathological findings also supported all our other findings. Dragon fruit extract was protected against indomethacin-induced ulcer damage by decreased MDA levels, increased GSH levels, and inhibition of Caspase 3, BAX, and Cox-2, and activation of Cox-1. PRACTICAL APPLICATIONS: People of all ages around the world suffer from gastric ulcer which is one of the most common gastrointestinal ailments. The etiological factors of the disease are using of cigarette and alcohol, nutritional deficiencies, infections, and using non-steroidal anti-inflammatory drugs which use frequent and indiscriminate. Indomethacin is one of the NSAIDs and is commonly preferred to induce ulcer modeling in rats due to its gastric toxicity potential. Current anti-ulcer drugs have many serious side effects. Patients who suffered from gastric ulcer tend to discontinue the drug because of side effects. Therefore, patients need new agents that are non-toxic, have few side effects, and are easily accessible anti-ulcer drugs. Dragon fruit, as a medicinal herb, is highly valuable and widely used in traditional medicine, and may provide gastroprotective activity. Studies have shown that H. polyrhizus has antioxidant activities. We consider the effects of dragon fruit extract (DFE) to be a therapeutic drug for an indomethacin-induced ulcer model.

The effects of mucosal media on some pathogenic traits of Crohn's disease-associated Escherichia coli LF82

Aim: Adherent-invasive Escherichia coli (AIEC) pathovar has been identified in intestinal mucosa of patients with Crohn's disease. Our aim was to compare the impact of sterile mucosal media (Muc-M) originated from different parts of the intestine on some pathogenic traits of AIEC LF82 strain. Materials & methods: Muc-M composed of certain rates of cell culture medium or M63 minimal medium and mucosal contents obtained from different part of intestine were designed for cell-infection experiments and biofilm-formation assays. Results: The results showed that Muc-M reduced usually pathogenic properties of AIEC LF82. However, LF82 adhesion, invasion and specific biofilm formations were markedly higher in Muc-MCR than those in Muc-MIR . Conclusion: In this context, the findings of present study could help the endeavors related to determining molecular targets for AIEC bacteria.

Alpha-lipoic acid inhibits peridural fibrosis following laminectomy through the inactivation of TGF-β1, PDGF, PAI-1 and IL-6 expressions

AIM

The objective of this study was to investigate the antifibrotic effect of parenteral administration of alpha-lipoic acid (ALA), which has been reported to reduce fibrosis in the liver, oral mucosa, and peritoneum, in laminectomized rabbits as a potential candidate for the prevention of peridural fibrosis.

MATERIAL AND METHODS

Twelve adult New Zealand white male rabbits were divided into control (n=6) and ALA treatment groups (n=6). Laminectomy of the lumbar spine was performed in all animals, and ALA was administered intramuscularly in six rabbits composing the treatment group. Total RNA obtained from the paraffin-embedded tissues was analyzed for transforming growth factor-β1 (TGF-β1), plateletderived growth factor (PDGF), plasminogen activator inhibitor-1 (PAI-1) and interleukin-6 (IL-6).

RESULTS

mRNA investigations showed that TGF-β1, PDGF, PAI-1 and IL-6 gene expressions, which constitute strong evidence for the development of fibrosis, were significantly lower in the treatment group compared with the results obtained from the control group. According to the histological peridural grading, the ALA-treated group showed significantly less peridural fibrosis than the control group.

CONCLUSION

Intramuscular administration of ALA is a promising treatment for the prevention of peridural fibrosis in the postoperative period.

Roles of beta2-adrenergic receptor gene polymorphisms in a Turkish population with obstructive sleep apnea syndrome or obesity

We determined the distribution of the Arg16Gly and Gln27Glu polymorphisms of the beta-2 adrenergic receptor gene (ADRB2) in patients with obstructive sleep apnea syndrome as well as a control group in Northeastern Turkey. A total of 52 patients diagnosed with obstructive sleep apnea in a sleep laboratory and 78 control subjects were examined. Peripheral blood samples were taken from patients diagnosed with obstructive sleep apnea by polysomnography. DNA was extracted from blood samples and amplified using polymerase chain reaction. Amplification products were digested with restriction enzymes to investigate gene polymorphisms. Restriction products were extracted from agarose gel electrophoresis and polymorphisms were analyzed using gel images. The Arg16Gly polymorphism was observed in 18 of 52 patients and in 23 of 78 controls. The Gln27Glu polymorphism was observed in 21 of 52 patients and in 28 of 78 controls. In conclusion, there was no correlation among polymorphic frequencies between patient and control groups. Based on the results, these polymorphisms do not contribute to the clinical diagnosis of this syndrome. However, the distribution of Arg16Gly vs Gln27Glu polymorphisms may contribute to obesity in patients with a body mass index greater than 30 (P < 0.05). Different results may be obtained if the parameters of obstructive sleep apnea disease are changed.