Derivatives of 6-Nitrobenzimidazole Inhibit Fructose-Mediated Protein Glycation and Intracellular Reactive Oxygen Species Production

BACKGROUND

Benzimidazoles are important pharmacophores in drug discovery, and currently its derivatives such as flubendazole, omeprazole, and astemizole are used for the treatment of anthelmintic, ulcerative, and histaminic diseases, respectively.

OBJECTIVES

The aim of the current study was to investigate the antiglycation activity of nitrobenzimidazole derivatives against fructose-mediated human serum albumin (HSA) glycation. The study was also aimed at investigating the effects of newly identified antiglycation inhibitors on AGEsinduced intracellular reactive oxygen species (ROS) production, and associated impaired proliferation of the hepatocytes.

METHODS

The present study focuses on the antiglycation activity of 6-nitrobenzimidazole derivatives 1-13 in in-vitro human serum albumin (HSA)- fructose model. These derivatives were also identified as non-toxic against 3T3 mouse fibroblast cell-line in MTT-based assay. The effect of the most promising derivative 5, 4-(6-nitro-1H-benzimidazol-2-yl)-1,2,3-benzenetriol, was studied in a dose dependent manner, co-incubated with fructose-derived AGEs (0- 200 μg/mL) on rat hepatocytes proliferation and associated intracellular generation of ROS via MTT-based assay and DCFHDA technique, respectively.

RESULTS

We found that derivative 5 ameliorates the elevated intracellular oxidative stress and associated diminished proliferation of the hepatocytes in response to AGEs.

CONCLUSION

In conclusion, we identified novel 6-nitrobenzimidazole derivatives as antiglycation agents through in-vitro, and cell-based models.

2-Arylquinazolin-4(3H)-ones: Inhibitory Activities Against Xanthine Oxidase

2-Arylquinazolin-4(3H)-ones (1-25) were synthesized, and evaluated for their xanthine oxidase inhibitory activity. Significant to moderate activities were exhibited by the compounds 1-3, 7, 9, 13-15, 19-21, and 23 with IC50 between 2.80 - 28.13 µM as compared to the standard allopurinol (IC50 (IC50 = 2.01 ± 0.01 µM). Compounds 4-6, 8, 11-12, 16-18, 22, and 24 demonstrated a weak activity with IC50 values 44.60 - 112.60 µM. Nonetheless, compounds 10 and 25 did not show any activity. Amongst all derivatives, compound 2, containing a C-4´ dimethylamino group, was the most potent inhibitor of the enzyme with an IC50 value comparable to the standard. Kinetics studies on the most active compounds (2, 7, 9, 14, 15, 19, and 20) were conducted in order to determine their modes of inhibition and dissociation constants Ki. Some of the compounds of 2-arylquinazolin-4(3H)-one series were thus identified as potential leads for further studies towards the treatment of hyperuricemia and gout.

New isatin derivative inhibits neurodegeneration by restoring insulin signaling in brain

Diabetes is associated with neurodegeneration. Glycation ensues in diabetes and glycated proteins cause insulin resistance in brain resulting in amyloid plaques and NFTs. Also glycation enhances gliosis by promoting neuroinflammation. Currently there is no therapy available to target neurodegenration in brain therefore, development of new therapy that offers neuroprotection is critical. The objective of this study was to evaluate mechanistic effect of isatin derivative URM-II-81, an anti-glycation agent for improvement of insulin action in brain and inhibition of neurodegenration. Methylglyoxal induced stress was inhibited by treatment with URM-II-81. Also, Ser473 and Ser9 phosphorylation of Akt and GSK-3β respectively were restored by URM-II-81. Effect of URM-II-81 on axonal integrity was studied by differentiating Neuro2A using retinoic acid. URM-II-81 restored axonal length in MGO treated cells. Its effects were also studied in high fat and low dose streptozotocin induced diabetic mice where it reduced RBG levels and inhibited glycative stress by reducing HbA1c. URM-II-81 treatment also showed inhibition of gliosis in hippocampus. Histological analysis showed reduced NFTs in CA3 hippocampal region and restoration of insulin signaling in hippocampii of diabetic mice. Our findings suggest that URM-II-81 can be developed as a new therapeutic agent for treatment of neurodegenration.

Interseason variability of a functional movement test, the 9+ screening battery, in professional male football players

BACKGROUND

The Nine Plus screening battery test (9+) is a functional movement test intended to identify limitations in fundamental movement patterns predisposing athletes to injury. However, the interseason variability is unknown.

AIM

To examine the variability of the 9+ test between 2 consecutive seasons in professional male football players.

METHODS

Asymptomatic Qatar Star League players (n=220) completed the 9+ at the beginning of the 2013 and 2014 seasons. Time-loss injuries in training and matches were obtained from the Aspetar Injury and Illness Surveillance Program. No intervention was initiated between test occasions.

RESULTS

A significant increase in the mean total score of 1.6 points (95% CI 1.0 to 2.2, p<0.001) was found from season 1 (22.2±4.1 (SD)) to season 2 (23.8±3.3). The variability was large, as shown by an intraclass correlation coefficient (ICC) of 0.24 (95% CI 0.11 to 0.36) and a minimal detectable change (MDC) of 8.7 points. Of the 220 players, 136 (61.8%) suffered a time-loss injury between the 2 tests. There was an improvement in mean total scores in the injured (+2.0±0.4 (SE), p<0.001) group but not in the uninjured group (+0.9±0.5, p=0.089). The variability from season 1 to season 2 was large both in the injured (ICC 0.25, 0.09 to 0.40, MDC 8.3) and uninjured (ICC 0.24, 0.02 to 0.43, MDC 9.1) groups.

CONCLUSIONS

The 9+ demonstrated substantial intraindividual variability in the total score between 2 consecutive seasons, irrespective of injury. A change above 8 points is necessary to represent a real change in the 9+ test between seasons.

Expression and Immunohistochemical Localisation of the Gβγ-activated and Calcineurin-Inhibited Adenylyl Cyclase Isoforms in Rat Articular Chondrocytes

OBJECTIVE

To determine the expression and localisation of the Gβγ-activated adenylyl cyclase (AC) isoforms 2, 4, and 7 and calcineurin-inhibited AC isoform 9 in rat articular chondrocytes.

STUDY DESIGN

Experimental study.

PLACE AND DURATION OF STUDY

Jumma Research Laboratory and Histology Laboratory, The Aga Khan University, Karachi, from 2009 to 2011.

METHODOLOGY

Fresh slices of articular cartilage were taken from various synovial joints of rats of different age groups. The expression of AC isoforms was determined by RT-PCR and immunohistochemistry was performed to localise these isoforms in articular chondrocytes. Tissue sections were processed for immunostaining with respective antibodies. The color was developed by diaminobenzidine.

RESULTS

All the studied AC isoforms were found to be differentially expressed in different zones of the rat articular cartilage. Generally, expression of all AC isoforms studied increased with age. The expression of the AC isoforms through PCR was almost consistent with the localisation of these isoforms by immunohistochemistry.

CONCLUSION

These data add to the information about signalling cascades possibly involved in articular chondrocytes. Variable expression of AC isoforms 2, 4, 7, and 9 suggest a role for the signalling cascades regulated by the AC isoforms in articular chondrocytes.

Islet autotransplantation in a patient with hypercoagulable disorder

Total pancreatectomy and islet auto transplantation is a good option for chronic pancreatitis patients who suffer from significant pain, poor quality of life, and the potential of type 3C diabetes and pancreatic cancer. Portal vein thrombosis is the most feared complication of the surgery and chances are increased if the patient has a hypercoagulable disorder. We present a challenging case of islet auto transplantation from our institution. A 29-year-old woman with plasminogen activator inhibitor-4G/4G variant and a clinical history of venous thrombosis was successfully managed with a precise peri- and post-operative anticoagulation protocol. In this paper we discuss the anti-coagulation protocol for safely and successfully caring out islet transplantation and associated risks and benefits.

Cognitive status is a determinant of health resource utilization among individuals with a history of falls: a 12-month prospective cohort study

SUMMARY

Falls are a costly public health problem worldwide. The literature is devoid of prospective data that identifies factors among fallers that significantly drive health care resource utilization. We found that cognitive function--specifically, executive functions--and cognitive status are significant determinants of health resource utilization among older fallers.

INTRODUCTION

Although falls are costly, there are no prospective data examining factors among fallers that drive health care resource utilization. We identified key determinants of health resource utilization (HRU) at 6 and 12 months among older adults with a history of falls. Specifically, with the increasing recognition that cognitive impairment is associated with increased falls risk, we investigated cognition as a potential driver of health resource utilization.

METHODS

This 12-month prospective cohort study at the Vancouver Falls Prevention Clinic (n = 319) included participants with a history of at least one fall in the previous 12 months. Based on their cognitive status, participants were divided into two groups: (1) no mild cognitive impairment (MCI) and (2) MCI. We constructed two linear regression models with HRU at 6 and 12 months as the dependent variables for each model, respectively. Predictors relating to mobility, global cognition, executive functions, and cognitive status (MCI versus no MCI) were examined. Age, sex, comorbidities, depression status, and activities of daily living were included regardless of statistical significance.

RESULTS

Global cognition, comorbidities, working memory, and cognitive status (MCI versus no MCI ascertained using the Montreal Cognitive Assessment (MoCA)) were significant determinants of total HRU at 6 months. The number of medical comorbidities and global cognition were significant determinants of total HRU at 12 months.

CONCLUSION

MCI status was a determinant of HRU at 6 months among older adults with a history of falls. As such, efforts to minimize health care resource use related to falls, it is important to tailor future interventions to be effective for people with MCI who fall.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01022866.

Development of new UV-vis spectroscopic microwave-assisted method for determination of glucose in pharmaceutical samples

A new UV-Visible spectroscopic method assisted with microwave for the determination of glucose in pharmaceutical formulations was developed. In this study glucose solutions were oxidized by ammonium molybdate in the presence of microwave energy and reacted with aniline to produce a colored solution. Optimum conditions of the reaction including wavelength, temperature, and pH of the medium and relative concentration ratio of the reactants were investigated. It was found that the optimal wavelength for the reaction is 610 nm, the optimal reaction time is 80s, the optimal reaction temperature is 160°C, the optimal reaction pH is 4, and the optimal concentration ratio aniline/ammonium molybdate solution was found to be 1:1. The limits of detection and quantification of the method are 0.82 and 2.75 ppm for glucose solution, respectively. The use of microwaves improved the speed of the method while the use of aniline improved the sensitivity of the method by shifting the wavelength.

Is there a role for neurotrophic factors and their receptors in augmenting the neuroprotective effect of (-)-epigallocatechin-3-gallate treatment of sciatic nerve crush injury?

This study analyzed and compared the effects of EGCG treatment on the expression of NTFs and NTF receptors expression in the sciatic nerve and the L3-L6 spinal cord segments at the early phase of regeneration following sciatic nerve crush injury. Analysis of BDNF, GDNF and NT3 neurotropic factors and Trk-B, Trk-C and NGFR-p75 receptors in neurons in the spinal cord of CRUSH and CRUSH + EGGC rats showed significant (p < 0.0001) decrease compared to NAÏVE and SHAM at day 1, 3, 7 and 14 after nerve injury. EGCG treatment significantly (p < 0.0001) increased the BDNF, GDN, NT3, Trk-B, Trk-C and NGFR-p75 immunostaining in the L3-L6 spinal cord compared to CRUSH animals. Also, EGCG treatment significantly increased the Trk-B protein concentration and Trk-B, NT3 and Trk-C gene expression in the spinal cords compared to CRUSH group. However, at day 1 and 3 post nerve injury, EGCG treatment significantly decreased the NGFR-p75 expression compared to CRUSH rats. In the sciatic nerve, EGCG treatment significantly (p < 0.01) increased the Trk-B and NGFR-p75 protein concentration in the controls. EGCG treatment significantly (p < 0.0001) increased the Trk-B, Trk-C and NGFR-p75 mRNA gene expressions in the sciatic nerves compared to CRUSH group. Only at day 1, CRUSH + EGCG animals displayed significant rise in the sciatic nerves NT3 gene expression compared to CRUSH group. Our data suggest that the EGCG neuroprotective effect on the spinal cord neurons may be mediated through the modulation of NTFs and NTF receptors following nerve crush injury in a rat model.

Use of Automated Bone Age for Critical Growth Assessment

BACKGROUND

We compared the variability of bone age (BA) rating between clinicians and an automated system in children with congenital adrenal hyperplasia (CAH).

METHOD

A total of 126 radiographs assessed by 3 clinicians blinded to patient details using Greulich and Pyle (GP) (readers 1, 2, and 3) and BoneXpert (BX).

RESULTS

Comparing BA rating with each other, the mean of the absolute differences varied from 0.42 ± 0.53 years (reader 1 and BX) to 0.57 ± 0.58 years (reader 2 and reader 3), P = .368. Comparing ratings that were consistent with all 4 methods (within 1 year of each other, 93/126, 74%) and the remaining, "outliers" (33/126, 26%), the outliers were younger (P = .003), smaller (height, P = .011, weight, P = .000), and prepubertal (P = .001).

CONCLUSION

The variability of BA rating in CAH children is similar whether performed by clinicians or an automated system. The greatest variability was in prepubertal children.

Effect of small donor weight and donor-recipient weight ratio on the outcome of liver transplantation in children

A small donor weight is a risk factor for HAT with potential for graft loss. To test this hypothesis, we evaluated outcomes of pediatric liver transplants utilizing donors <20 kg using the UNOS database from 01/2003 to 01/2012 (n = 1311). All isolated liver transplants with whole organ grafts were included. Recipients were divided into four groups based on donor weight: group 1, donor weight <5 kg (n = 34 [2%]); group 2, 5-10 kg (431 [33%]); group 3, 10-15 kg (560 [43%]); and group 4, 15-20 kg (286 [22%]). Actuarial patient survival for the first year post-transplant was significantly lower in groups 1 and 2 compared to groups 3 and 4 (p = 0.002), similarly the one-yr graft function (p < 0.0001). The difference was due to graft loss within the first month for groups 1 and 2. HAT was significantly higher in groups 1 and 2 compared to others (p = 0.0006). Logistic regression analysis demonstrated donor weight as the most predictive factor with analysis of the ROC curve showing a cutoff point at 7.8 kg. The donor-recipient weight ratio did, in none of the models, gain statistical significance.

Studies on chemistry, spectroscopy and antioxidant activities of chromium(III)-hydrazide complexes

Acid hydrazides are vital chemical entities due to their biological activities. Upon complexation with certain metal ions, their biological activities are known to be positively enhanced. The present work describes the synthesis of Cr(III)-hydrazide complexes, and their structural, spectroscopic and antioxidant properties to reveal their chemistry and biochemistry. Physical (magnetic moment, conductivity measurements), analytical (C, H, N and Cr analysis) and spectral (EI-Mass, FTIR) techniques are used for the characterization of synthesized compounds. All Cr(III)-hydrazide complexes exhibit octahedral geometry with general formula [Cr(L)2(H2O)2]Cl3. In these complexes, the hydrazide ligands are coordinated via carbonyl oxygen and terminal amino nitrogen in a bidentate fashion. All Cr(III)-hydrazide complexes were screened for in vitro diphenyldipicryl hydrazine (DPPH), superoxide dismutase and nitric oxide radical scavenging activities. Majority of the Cr(III)-hydrazide complexes were found to be more potent scavengers than their uncoordinated hydrazide ligands. This study demonstrates an interesting structure-activity relationship (SAR) which is presented here.

Developing trends in the intestinal transplant waitlist

The United Network for Organ Sharing database was examined for trends in the intestinal transplant (ITx) waitlist from 1993 to 2012, dividing into listings for isolated ITx versus liver-intestine transplant (L-ITx). Registrants added to the waitlist increased from 59/year in 1993 to 317/year in 2006, then declined to 124/year in 2012; Spline modeling showed a significant change in the trend in 2006, p < 0.001. The largest group of registrants, <1 year of age, determined the trend for the entire population; other pediatric age groups remained stable, adult registrants increased until 2012. The largest proportion of new registrants were for L-ITx, compared to isolated ITx; the change in the trend in 2006 for L-ITx was highly significant, p < 0.001, but not isolated ITx, p = 0.270. New registrants for L-ITx, <1 year of age, had the greatest increase and decrease. New registrants for isolated ITx remained constant in all pediatric age groups. Waitlist mortality increased to a peak around 2002, highest for L-ITx, in patients <1 year of age and adults. Deaths among all pediatric age groups awaiting L-ITx have decreased; adult L-ITx deaths have dropped less dramatically. Improved care of infants with intestinal failure has led to reduced referrals for L-ITx.

Genotype CC of rs12979860 is providing protection against infection rather than assisting in treatment response for HCV genotype 3a infection

Recent discovery of single-nucleotide polymorphisms located in the upstream region of interleukin-28B (IL28B) has shown association with interferon (IFN) treatment response especially in hepatitis C virus (HCV) genotype 1-infected patients. Pakistan, being the country with second highest prevalence of HCV with predominantly 3a genotype infection, bears a significant disease burden. The present study was conducted to evaluate the effect of rs12979860 genotypes on treatment response in HCV-3a-infected patients. This study shows that the CC genotype is providing protection against infection to HCV. But once infected, the CC genotype patients show viral persistence following IFN therapy. The TT genotype is assisting the 3a patients in viral clearance after IFN treatment. To our knowledge, this is the first study showing rs12979860 genotype association with IFN response in Pakistani HCV-3a-infected patients.

Hepatic explant pathology of pediatric intestinal transplant recipients previously treated with omega-3 fatty acid lipid emulsion

OBJECTIVE

To evaluate and compare the biochemical and histologic effect of parenteral fish oil lipid emulsion that is rich in omega-3 polyunsaturated fatty acids (O3FAs), Omegaven (Fresenius Kabi AG, Bad Homburg, Germany) with standard omega-6 polyunsaturated fatty acid (O6FA) parenteral nutrition.

STUDY DESIGN

Comparison of hepatic explant pathology and biochemical outcome on pediatric patients with intestinal failure treated with either parental O3FA or O6FA who had received a liver-inclusive intestine transplant.

RESULTS

Seven liver-inclusive intestinal transplants were performed in 7 patients who received O3FA for a mean of 62% ± 13% of total patient life-span (16.1 ± 7.0 months) before transplant. Median total bilirubin fell from 6.9 mg/dL at the start of treatment to 0.7 mg/dL at the time transplant (P < .02), which was a significant decrease compared with the similarly matched O6FA cohort (P = .012). All 7 of the 03FA-treated patients received a liver-inclusive intestinal transplant had advanced fibrosis (stage 3 or 4) noted on explant pathologic examination, despite a resolution of cholestasis at the time of transplant. Histologic inflammatory scores were lower (P = .056) in the 03FA group with similar degrees of advanced fibrosis as in the O6FA group.

CONCLUSIONS

In a matched comparison of patients undergoing intestinal transplantation with a history of extended O3FA lipid emulsion therapy that successfully reversed hyperbilirubinemia, significant hepatic fibrosis was present in the explanted livers despite a reduction in inflammation. This result confirms concern that the use of O3FA may have a limited role in altering the development of hepatic fibrosis from parenteral nutrition.

Synthesis, crystal structure, DFT studies and evaluation of the antioxidant activity of 3,4-dimethoxybenzenamine schiff bases

Schiff bases of 3,4-dimethoxybenzenamine 1-25 were synthesized and evaluated for their antioxidant activity. All the synthesized compounds were characterized by various spectroscopic techniques. In addition, the characterizations of compounds 13, 15 and 16 were supported by crystal X-ray determinations and their geometrical parameters were compared with theoretical DFT calculations at the B3LYP level of theory. Furthermore, the X-ray crystal data of two non-crystalline compounds 8 and 18 were theoretically calculated and compared with the practical values of compounds 13, 15, 16 and found a good agreement. The compounds showed good DPPH scavenging activity ranging from 10.12 to 84.34 μM where compounds 1-4 and 6 showed stronger activity than the standard n-propyl gallate. For the superoxide anion radical assay, compounds 1-3 showed better activity than the standard.