Genetic variants of folate metabolism and the risk of multiple sclerosis

BACKGROUND AND AIMS

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) of unknown cause. Alterations in one-carbon metabolism have impact in the pathophysiology by genetic susceptibility to MS and increased the risk of MS. The aim of this study was to investigate the contribution of the gene polymorphism on Methylenetetrahydrofolate Reductase (MTHFR), Methionine Synthase Reductase (MTRR), Methionine Synthase (MTR) enzymes and of the essential factors (homocysteine, Hcy; cysteine, Cys; and vitamin B12, VitB12) in folate metabolism.

METHODS

Eligible MS patients (n = 147) and health controls (n = 127) were participated. The gene polymorphisms were analyzed by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and the levels of plasma Hcy, Cys and VitB12 were measured by Enzyme Linked Immunuabsorbent Assay (ELISA).

RESULTS AND CONCLUSION

Our results showed that the levels of Hcy and VitB12 were lower and the levels of Cys were higher in MS compared to controls. The observation of high Cys values in all 3 gene polymorphisms suggests that the transsulfiration pathway of Hcy is directed towards Cys formation since the methionine synthesis pathway does not work. We could not find any association with all gene polymorphisms with the risk of MS. The T allele of MTHFR C677T and G allele of MTR A2756G are risk factors for serum Cys level on MS. As for MTR A2756G, serum vitB12 was observed in MS patients with G allele.

Iatrogenic botulism cases after gastric and axillary application of botulinum toxin and review of literature

INTRODUCTION

Iatrogenic botulism is a rare, serious disease that progresses with descending paralysis and develops after cosmetic or therapeutic botulinum toxin-A (BoNT-A) application.

CASE PRESENTATIONS

In this case series; six cases of iatrogenic botulism followed up in our center are presented. Four of these developed after gastric BoNT-A and two after axillary BoNT-A application.

RESULTS

The most important cause for the disease was the use of unlicensed products and high-dose toxin applications. The first symptoms were blurred vision, double vision, difficulty in swallowing, and hoarseness. Symptoms appeared within 4-10 days after the application of BoNT-A. Symptoms progressed in the course of descending paralysis in the following days with fatigue, weakness in extremities and respiratory distress. Diagnosis was based on patient history and clinical findings. The main principles of foodborne botulism therapy were applied in the treatment of iatrogenic botulism. If clinical worsening continued, regardless of the time elapsed after BoNT-A application, the use of botulinum antitoxin made a significant contribution to clinical improvement and was recommended.

CONCLUSIONS

Routine and new indications for BoNT-A usage are increasing and, as a result, cases of iatrogenic botulism will be encountered more frequently. Physicians should be alert for iatrogenic botulism in the follow-up after BoNT-A applications and in the differential diagnosis of neurological diseases that are presented with similar findings.

Association of vitamin D receptor polymorphisms with vitamin D and calcium levels in Turkish multiple sclerosis patients

Aim: The present study was conducted to assess the impact of gene (vitamin D receptor [VDR] polymorphisms) - environment (serum vitamin D and calcium levels) interaction on multiple sclerosis (MS) risk. Materials & methods: FokI, BsmI, TaqI and ApaI genotyping were performed in 149 MS patients and 127 controls. We measured serum vitamin D and calcium levels. Results: No significant difference between VDR polymorphisms and MS risk was detected. In patients with FokI ff, BsmI Bb, TaqI Tt and ApaI AA genotypes, vitamin D levels were statistically higher. Serum calcium levels were significantly lower in patients with FokI FF, Ff, all BsmI and TaqI genotypes and ApaI AA and Aa genotypes. Conclusion: No significant association was found between VDR polymorphisms with MS risk.

Individual susceptibility has a major impact on strong association between oxidative stress, defence systems and Parkinson's disease

Oxidative stress plays an important role in the degeneration of dopaminergic neurons, which causes Parkinson's disease (PD). Oxidative stress products, antioxidant and their balance have important roles in the development of oxidative stress-based PD. The impact of reactive oxygen species (ROS) and defence systems can be altered by genetic polymorphisms, and thus the risk of PD may also be affected. We aimed to investigate the possible association of individual susceptibility with the development of oxidative stress-based PD. For this purpose, we measured serum levels of folic acid, homocysteine, Vitamin B6 and B12 that play roles in folate-dependent one-carbon pathway, oxidant or antioxidant enzymes (NADPH oxidase, MnSOD, GPX), 8-OHdG and repair enzymes (OGG1, XRCC1 and MTH1) by ELISA, and analysed related gene polymorphisms by PCR-RFLP. XRCC1, ROS, NADPH and folic acid levels were found to be statistically higher in patients than controls. XRCC1, MnSOD and GPX activities were increased. We observed higher levels of 8-OHdG in patients with MnSOD and XRCC1 mutant genotypes and higher XRCC1 levels in patients with NOX p22 fox mutant genotypes rather than controls. We suggest that routinely clinical validation of major oxidative stress-related biomarkers will be a good approach to manage detrimental effects of PD.

Oxidative stress gene polymorphisms may have an impact in the development of ischemic stroke

BACKGROUND

Antioxidants are responsible for detoxification of harmful effects of reactive oxygen species. Genetic factors may influence antioxidant activity as a result of polymorphisms on antioxidant enzymes. These polymorphisms can be risk in ischemic stroke (IS) risk. IS is a disorder with genetic and environmental factors contributing to overall risk. Although a few studies have been conducted, there have been no reports on catalase (CAT C262T), manganese superoxide dismutase (MnSOD Ala16Val) and glutathione peroxidase 1 (GPX1 Pro198Leu) gene polymorphisms and IS risk.

METHODS

We aimed to perform a case-control study to increase the awareness of the impact of oxidative stress (OS) gene polymorphism in the development of IS. A restriction fragment length polymorphism-polymerase chain reaction was used to determine genotypes. The interactions between genes and smoking and possible risk factors were evaluated.

RESULTS

An approximately four-fold higher IS risk was found in patients with the Val allele compared to the Ala allele. Smoking was a risk factor in the development of IS for CAT TT and MnSOD Ala/Val genotypes; we found a 3.5- to 5.5-fold higher IS risk in CAT TT and MnSOD Ala/Val genotypes. Different logistic regression models were performed for possible risk factors (smoking, body mass index, low-density lipoprotein and diabetes mellitus). The IS risk increases statistically significant only with age by multiple logistic regression analysis. CAT gene polymorphisms in IS patients were not different from controls.

CONCLUSIONS

It is unlikely that CAT and GPX1 single nucleotide polymorphisms are risk factors for IS. The results of the present study show that smoking may be a risk factor for IS risk in patients with MnSOD mutant genotypes.

Analysis of multiple sclerosis patients with electrophysiological and structural tests

We aimed to analyze the effects of progressive myelin loss and neurodegeneration seen in patients with multiple sclerosis (MS) on visual tract with electrophysiological and structural tests. Fifty-one patients diagnosed with MS in the Neurology Department were followed up in neuro-ophthalmology outpatient clinic irrespective of their visual symptoms, and were included in our study. The patients were classified as the ones with the history of optic neuritis (group II) and ones without the history (group I) of optic neuritis. The data, including clinical presentation, retinal nerve fiber layer thickness (RNFLT) measurements, pattern visual evoked potential (pVEP) and flash electro retino grams (ERG) test results, were recorded. In our study, comparison of pVEP test latencies of groups I and II with each other, and with those of healthy subjects revealed statistically significant differences (p < 0.05). The analysis of rod functions on ERG did not show any significant changes (p > 0.05). However, both groups showed significantly decreased cone b-wave amplitudes, elongation of latencies, and decreased flicker amplitudes on cone and flicker potentials obtained after light adaptation (p < 0.05). There was significant thinning in RNFLT of the both groups when compared to the normal standards. The difference between two groups was statistically significant (p < 0.05). Axon loss is seen in the optic nerve with subclinical or acute optic neuritis in patients with MS. RNFLT analysis and electrophysiological tests are of great importance in diagnosis of MS, as well as to determine progression and to direct neuroprotective therapy in patients diagnosed with MS. Objective analysis methods gain more importance in the diagnosis and follow-up of MS patients, parallel to technological advancements.

The association of IL-18 gene promoter polymorphisms and the levels of serum IL-18 on the risk of multiple sclerosis

OBJECTIVES

Multiple sclerosis is an inflammatory condition of the central nervous system whose etiology is influenced by immunologic, genetic, and environmental factors. Aim of the present study was to determine if any relation exists between IL-18 -137C/G and -607C/A gene promoter polymorphisms on the individual susceptibility of multiple sclerosis and also to investigate the possible effect of IL-18 activity regarding this kind of polymorphism and MS.

PATIENTS AND METHODS

113 patients with clinically definite MS and 135 ethnically-matched controls were participated in this study. IL-18 -137C/G and -607C/A gene promoter polymorphisms were analyzed by Sequence Specific Polymerase Chain Reaction (SS-PCR), while levels of serum IL-18 were measured by Enzyme Linked Immunoassay Assay (ELISA) in patients with MS and healthy controls.

RESULTS

Our results showed that the IL-18 -607AA genotype indicated 6 times higher risk in the development of MS (OR=6.883; 3.17-14.96; p<0.001). According to our findings, smoking seems to be an important confounding factor in MS patients with carrying IL-18 -607 AA and CA+AA genotypes. However, no meaningful association was found with IL-18 -137C/G gene promoter polymorphism.

CONCLUSION

In conclusion, we suggest that IL-18 -607C/A gene promoter polymorphism is a major genetic factor for determining individual susceptibility to MS, where smoking status also increases the risk of MS.

The impact of detoxifying and repair gene polymorphisms on oxidative stress in ischemic stroke

Stroke is a multifactorial disease caused by the combination of certain risk factors and genetic factors. There are possible risk factors having important role in the pathogenesis of stroke. The most important environmental factors are cigarette smoking and oxidative stress which have different sources. GST (M1, T1, P1) have major roles in detoxification of the products of oxidative stress and they are polymorphic. DNA damages can also be repaired by repair enzymes such as OGG1 and XRCC1 which are highly polymorphic and have pivotal roles in repair systems. In the present study, we investigated that polymorphisms in genes involved in detoxification and DNA-repair pathways might modify the individual's risk for ischemic stroke. Furthermore, the products of oxidative stress and antioxidant capacity were measured and the impact of gene polymorphism on them was evaluated. Our data showed that OGG1 Ser326Cys and XRCC1 Arg399Gln gene polymorphisms had impacts on the development of stroke.

Proximal protection with hybrid stent, a safer combination for carotid artery stenting against carotid endarterectomy?

AIM

Carotid revascularization is an established theurapeutic modality in preventing stroke and death among patients with severe carotid stenosis. Although carotid endarterectomy remains as the primary option, carotid stenting is accepted as an alternative for patients with high risk for carotid endarterectomy. Recently published reports have better results with proximal protection devices when compared with distal protection devices. These studies have revealed less microembolic signals and less periprocedural new ischemic lesions on diffusion weighted magnetic resonance imaging. Stent choice may be also important for these procedures as open cell stent design has advantage of better flexibility whereas closed cell systems have an advantage of better scaffolding. Hybrid stents which are composed of open cells in the proximal and distal part and closed cells in the middle may carry both advantages. The aim of this study is to demonstrate whether combination of proximal protection devices with hybrid stents can be a safe alternative for carotid stenting in terms of periprocedural and 30-day outcomes.

METHODS

Here we retrospectively evaluated 68 symptomatic carotid stenosis patients undergoing carotid stenting with hybrid stent (Cristallo Ideale®, Invatec s.r.l., Medtronic, Italy) and proximal protection device (MO.MA®, Invatec s.r.l., Medtronic, Italy).

RESULTS

Our results showed only 1 minor stroke in the periprocedural period and during the first 30-day after stenting, with no death or myocardial infarction.

CONCLUSION

Although our case number is not large, we propose that carotid stenting may be safer with utilization of proximal protection system and hybrid type carotid stents.

An overview on natural cholinesterase inhibitors--a multi-targeted drug class--and their mass production

Cholinesterase enzyme family consisting of acetylcholinesterase (AChE) and butrylcholinesterase (BChE) is important in pathogenesis of Alzheimer's disease (AD), explained by "cholinergic hypothesis". Accordingly, deficiency of the neuromediator called "acetylcholine" excessive amount of BChE has been well-described in the brains of AD patients. Consequently, cholinesterase inhibition has become one of the most-prescribed treatment strategies for AD. In fact, cholinesterase inhibitors have been also reported for their effectiveness in some other diseases including glaucoma, myasthenia gravies, as well as Down syndrome, lately. They play a role in the action of mechanism of insecticidal drugs such as carbamate derivatives as well as nerve gases such as malathion and parathion. All these utilizations can make them a multi-targeted drug class putting a special emphasis on AD therapy in the first place. Several inhibitors of cholinesterases with synthetic and natural origins are available in drug market; however, the reasons including side effects, relatively low bioavailability, etc. limit their uses in medicine and there is still a great demand to discover new cholinesterase inhibitors. Galanthamine, an alkaloid derivative isolated from snowdrop (Galanthus nivalis L.), is the latest anticholinesterase drug used against AD. Huperzine A, isolated from Huperzia serrata (Thunb.) Trev. is the most-promising drug candidate with potent anticholinesterase effect and it is a licensed anti-AD drug in China. In this review, a short introduction will be given on known cholinesterase inhibitors and, then, galanthamine and huperzine A will be covered in regard with their cholinesterase inhibitory potentials and mass productions by organic synthesis and in vitro culture techniques.

Early outcomes of carotid artery stenting

BACKGROUND AND AIM

Ischemic cerebrovascular events are the most common reason for patients to be bedridden and the third most common reason for death. Many studies in recent years have demonstrated that carotid artery stenting (CAS) may be an alternative to carotid endarterectomy (CEA). In this study, we aimed to report early outcomes of patients who were treated with CAS in our clinic and discuss practicability, advantages and safety of CAS.

METHODS AND FINDINGS

Eighty patients who underwent CAS between December 2009 and May 2011 were eligible. The mean age was 65 years (range, 49 - 89 years). Of the study group, 73.75% were males and 26.25% were female. The percentage of asymptomatic patients was 11.7%, and the remaining patients were symptomatic. A distal embolic protection device (Angioguard®) was used in 22% of the patients whereas, in the other patients (78%), a proximal blockage system (Mo.MA®) was used. Self-expandable hybrid stents were implanted in all patients and post-dilatation was performed after implantation. None of the patients suffered from stroke, myocardial infarction or death due to CAS during their hospital stay. The mean follow-up period was 10 months (range 2 - 18 months) after discharge. None of the patients had died or had a stroke, a transient ischemic attack (TIA), or a myocardial infarction during the follow-up period. Re-stenosis was not observed in the follow-up carotid Doppler ultrasonography; flow rates were within normal limits.

CONCLUSION

No major complication was observed during the early follow-up period in patients who underwent CAS in our clinic. Only 2 (2.5%) patients showed transient numbness and weakness and these did not lead to morbidity. In the management guide of extracranial carotid and vertebral artery diseases, CAS, in the light of recent studies, is recommended as an alternative to CEA in recommendations for revascularization. One of the important issues emphasized in this guide is the experience of centers. Very low complication rates after CAS suggested that, with suitable patient selection and an experienced team, similar results may be obtained.

Contemporary anticholinesterase pharmaceuticals of natural origin and their synthetic analogues for the treatment of Alzheimer's disease

Alzheimer's disease (AD), the most common form of dementia, is a degenerative and progressive neurological disorder characterized by deficit in the cholinergic transmission and formation of senile plaques containing beta-amyloid protein in the brain. Although complete pathology of the disease has not been fully elucidated yet, there are several treatment strategies for AD treatment. The complexity of AD is also due to involvement of several enzymes through its progression. Therefore, the most important therapeutic approach has emerged as inhibition of acetylcholinesterase (AChE), which is the key enzyme in the breakdown of acetylcholine. Another very attractive approach to lower beta-amyloid protein in fibrillar form has been the alpha- and beta-secretase inhibitors. On the other hand, recently, N-methyl-D-aspartate (NMDA) receptor antagonists have become a strong alternative, which has been approved to be effective in treatment of moderate to severe type of AD. Within the past few years, some pharmaceuticals have become available for clinical use; however, none of them have been shown to possess ability to discontinue the disease up to date. Hence, there is obviously a great need for discovery of new drug candidates of natural or synthetic origins for AD treatment. This review will cover AChE-inhibiting pharmaceuticals from plants and their synthetic derivatives including relevant patent literatures which may promise a future hope for AD treatment.

Surgery of carotid body tumour: 14 cases in 7 years

OBJECTIVE

The goal was to review our experience in the management of carotid body tumours.

MATERIAL AND METHODS

A retrospective study was performed of patients in whom carotid body tumour was diagnosed between 1998 and 2005. Data were retrieved from hospital discharge files.

RESULTS

Fourteen patients were operated on. There were five patients in Shamblin class I, 4 in class II, and 5 in class III. Duplex examination was performed in all patients. Computerized tomography scans were performed in eight (57%) patients and magnetic resonance imaging scans in five patients (36%). Angiography was performed in all patients, preoperative embolization was attempted in 5 (36%). The blood loss for these patients was not less than for those without embolization. Three patients (21%) had postoperative cranial nerve deficits. All the deficits resolved. The internal carotid artery was injured in two patients and the external carotid artery was injured in three patients (36%). No stroke occured.

CONCLUSION

Surgical resection is the treatment of choice for carotid body tumours. Observation of these tumours is not recommended because progressive growth is associated with increased risk of neurological deficits. Early surgical management is recommended to avoid neurological deficit due to a Shamblin class III tumour. We also do not recommend embolization.

Ultrasonic decalcification of calcified valve and annulus during heart valve replacement

A heavily calcified heart valve annulus increases the likelihood of sequelae after prosthetic valve replacement. Such sequelae include cerebral embolism, paravalvular leakage, valvular dysfunction, rhythm disturbance, hemolysis, communication of the heart chambers, and rupture of the posterior wall of the left ventricle. From January 1991 through June 1994, we performed heart valve replacement on 30 patients, using an ultrasonic surgical aspirator to remove calcific deposits. We placed aortic valve prostheses in 12 patients, mitral valve prostheses in 13 patients, and both aortic and mitral prostheses in 5 patients, after ultrasonic débridement of calcified annuli. All patients were re-examined 6 months after surgery: echocardiographic study showed no paravalvular leakage or valve-related complications. In our experience, ultrasonic decalcification of the annulus is superior to traditional methods. We advocate the use of ultrasonic débridement as an adjunctive tool in calcified heart valve replacement.

The effect of the male contraceptive agent gossypol acetic acid on mouse bone marrow cells in vivo: micronuclei and mitotic index

In this work the genotoxic effect of gossypol acetic acid (gossypol) was evaluated by determining the frequency of micronuclei and mitotic index in male mouse bone marrow cells in vivo. Bone marrow cells were collected at 24th hour after the single intraperitoneal (20, 40, and 80 micrograms/g) administration of gossypol. Polychromatic erythrocytes (PCEs) in the bone marrow were then evaluated with respect to micronuclei frequency. The dose-dependent increase in the micronuclei frequency was observed. However, when compared with the control group, the increase was not found to be significant (P > 0.05). Also the mitotic index values were not found to be different from those control values (P > 0.05). The results suggest that gossypol is not a clastogenic and mutagenic agent in mouse bone marrow cells in vivo.