Investigation of the Pharmacokinetic Properties and Theoretical Chemical Activities of 7,8-Dihydroxyflavone and 4'-Dimethylamino-7,8-Dihydroxyflavone

Purpose:

Flavonoids naturally exist in plants as secondary metabolites. In this study, the aim is to determine and compare the theoretical and in vivo chemical activities of 7,8-dihydroxyflavone (7,8-DHF) and 4'dimethylamino-7,8-dihydroxyflavone (4’-DMA-7,8-DHF), tyrosine receptor kinase B (TrkB) receptor agonist flavonoid molecules with reported potent neuroprotective effects.

background:

BDNF has been thought to be a potent therapeutic agent against neurological disorders via its receptor TrkB. However, BDNF has poor pharmacokinetic properties and cannot cross the blood-brain barrier. It has been demonstrated that 7,8-DHF and 4''-DMA-7,8-DHF can bind and activate TrkB receptors and pass the blood-brain barrier. It has been thought that 4''-DMA-7,8-DHF may be more potent than 7,8-DHF due to strong TrkB activity and supporting neurogenesis at lower concentrations. However, there is no detailed study on this yet.

Methods:

method was used for the theoretical chemical analysis. For the in vivo studies, 6-month-old Wistar rats were used in two groups (n=8). 7,8-DHF and 4’-DMA-7,8-DHF (5 mg/kg) were administered intraperitoneally (ip) to each group. Then, plasma samples were collected by carotid catheterization, and brain samples by the microdialysis technique were collected simultaneously for 12 h from awake rats. The level of 7,8-DHF and 4’-DMA-7,8-DHF in blood and brain samples were analyzed and their pharmacokinetics were determined.

objective:

Flavonoids naturally exist in plants as seconder metabolites. In this study, the aim is to determine and compare the theoretical and in vivo chemical activities of 7,8-DHF and 4’-DMA-7,8-DHF, tyrosine receptor kinase B (TrkB) receptor agonist flavonoid molecules with reported potent neuroprotective effects.

Results:

Theoretical calculations show that 7,8-DHF is slightly more stable than 4’-DMA-7,8-DHF. The in vivo pharmacokinetic results show that the maximum concentration of 7,8-DHF was about 48 ng/mL, whereas it was only 8 ng/mL for 4’-DMA-7,8-DHF.

Conclusion:

Our results suggest that the 4'-DMA-7,8-DHF is more unstable and is more prone to binding to TrkB than 7,8-DHF. On the other hand, the in vivo pharmacokinetic results show that 7,8-DHF is more stable than 4’-DMA-7,8-DHF when it is applied systemically at therapeutic concentrations.

result:

Theoretical calculations show that 7,8-DHF is slightly more stable than 4’-DMA-7,8-DHF. The in vivo pharmacokinetic results show that the maximum concentration of 7,8-DHF was about 48 ng/mL, whereas it was only 8 ng/mL for 4’-DMA-7,8-DHF.

other:

7.8-DHF seems more suitable for pharmacological applications.

Management of Biliary Complications in Liver Transplant Recipients with Duct-To-Duct Anastomosis: A Single-Center Experience

BACKGROUND

The aims of this study were to investigate biliary complications in liver transplant recipients with choledochocholedocho stomy anastomosis, to identify the risk factors for the development of such complications, and to evaluate the success of endoscopic approaches in liver transplant recipients.

METHODS

Between January 2013 and May 2021, a total of 238 patients with liver diseases underwent liver transplantation: 174 recipients undergoing choledochocholedochostomy anastomosis were included in the analysis.

RESULTS

Their median age was 54.0 years. The median posttransplant follow-up period was 29 months. Hepatitis B virus infection (33%) was the most common indication for liver transplantation. Most patients (87%) received living donor liver transplantation. The overall prevalence of posttransplant biliary complications was 31%. Anastomotic biliary strictures were the most common biliary complications (72%), followed by biliary leakage (13%). The median time between endoscopic retrograde cholangiography and liver transplantation was 4 months, with a mean of 3 ± 1.6 sessions. Endoscopic retrograde cholangiography-guided drainage and balloon dilation with or without stent placement was the most common treatment modalities for recipients with biliary strictures. The overall success rate of endoscopic treatment modalities was 83.3%, with 65% of the recipients exhibiting complete biochemical and endoscopic responses. The response did not differ significantly between living donor liver transplantation and cadaveric donor liver transplant recipients (P > .05). Three recipients required revision surgery for biliary complication repair. Six patients died due to biliary sepsis.

CONCLUSION

Biliary stricture and leakages were the most common biliary complications after liver transplantation. Endoscopic treatment was successful in most recipients.

High-dose dual therapy is effective as first-line treatment for Helicobacter pylori infection

BACKGROUND/AIMS

Although many regimens, including quadruple, sequential, and concomitant treatment, are used and recommended as first-line or rescue therapies for Helicobacter pylori infection, eradication rates are still below 90% in intention-to-treat analyses. Treatment protocols with substantially high eradication rates and low antibiotic resistance are needed. In this study, we investigated the efficacy of high-dose dual therapy as first-line treatment in a Turkish population.

MATERIALS AND METHODS

All patients underwent upper gastrointestinal endoscopy for the initial H. pylori status because of dyspeptic symptoms. All patients received a 14-day, high-dose dual therapy comprising rabeprazole (20 mg t.i.d.) and amoxicillin (1 g t.i.d.) for H. pylori eradication. H. pylori stool antigen tests of eradication were administered to all participants at least 4 weeks after the completion of the treatment.

RESULTS

The high-dose dual therapy demonstrated a 91.3% rate of successful eradication of H. pylori infection. Per-protocol success was 94.4% among female patients (n=51) and 89.6% among male patients (n=86); in terms of gender, the differences were not significant (p=0.310). No side effects were observed during the study in any patient. Six other patients did not take adequate doses of the treatment protocol.

CONCLUSION

High-dose dual therapy with rabeprazole and amoxicillin was highly effective and well tolerated as a first-line therapy for H. pylori eradication.