Paolo Zamboni

Oxidative Stress and Neurodegenerative Diseases: A Review of Upstream and Downstream Antioxidant Therapeutic Options

Free radicals are common outcome of normal aerobic cellular metabolism. In-built antioxidant system of body plays its decisive role in prevention of any loss due to free radicals. However, imbalanced defense mechanism of antioxidants, overproduction or incorporation of free radicals from environment to living system leads to serious penalty leading to neuro-degeneration. Neural cells suffer functional or sensory loss in neurodegenerative diseases. Apart from several other environmental or genetic factors, oxidative stress (OS) leading to free radical attack on neural cells contributes calamitous role to neuro-degeneration. Though, oxygen is imperative for life, imbalanced metabolism and excess reactive oxygen species (ROS) generation end into a range of disorders such as Alzheimer’s disease, Parkinson’s disease, aging and many other neural disorders. Toxicity of free radicals contributes to proteins and DNA injury, inflammation, tissue damage and subsequent cellular apoptosis. Antioxidants are now being looked upon as persuasive therapeutic against solemn neuronal loss, as they have capability to combat by neutralizing free radicals. Diet is major source of antioxidants, as well as medicinal herbs are catching attention to be commercial source of antioxidants at present. Recognition of upstream and downstream antioxidant therapy to oxidative stress has been proved an effective tool in alteration of any neuronal damage as well as free radical scavenging. Antioxidants have a wide scope to sequester metal ions involved in neuronal plaque formation to prevent oxidative stress. In addition, antioxidant therapy is vital in scavenging free radicals and ROS preventing neuronal degeneration in post-oxidative stress scenario.

Chronic cerebrospinal venous insufficiency in patients with multiple sclerosis

Background: The extracranial venous outflow routes in clinically defined multiple sclerosis (CDMS) have not previously been investigated. Methods: Sixty-five patients affected by CDMS, and 235 controls composed, respectively, of healthy subjects, healthy subjects older than CDMS patients, patients affected by other neurological diseases and older controls not affected by neurological diseases but scheduled for venography (HAV-C) blindly underwent a combined transcranial and extracranial colour-Doppler high-resolution examination (TCCS-ECD) aimed at detecting at least two of five parameters of anomalous venous outflow. According to the TCCS-ECD screening, patients and HAV-C further underwent selective venography of the azygous and jugular venous system with venous pressure measurement. Results: CDMS and TCCS-ECD venous outflow anomalies were dramatically associated (OR 43, 95% CI 29 to 65, p<0.0001). Subsequently, venography demonstrated in CDMS, and not in controls, the presence of multiple severe extracranial stenosis, affecting the principal cerebrospinal venous segments; this provides a picture of chronic cerebrospinal venous insufficiency (CCSVI) with four different patterns of distribution of stenosis and substitute circle. Moreover, relapsing-remitting and secondary progressive courses were associated with CCSVI patterns significantly different from those of primary progressive (p<0.0001). Finally, the pressure gradient measured across the venous stenosies was slightly but significantly higher. Conclusion: CDMS is strongly associated with CCSVI, a scenario that has not previously been described, characterised by abnormal venous haemodynamics determined by extracranial multiple venous strictures of unknown origin. The location of venous obstructions plays a key role in determining the clinical course of the disease.

A prospective open-label study of endovascular treatment of chronic cerebrospinal venous insufficiency

OBJECTIVE Chronic cerebrospinal venous insufficiency (CCSVI) is characterized by combined stenoses of the principal pathways of extracranial venous drainage, including the internal jugular veins (IJVs) and the azygous (AZY) vein, with development of collateral circles and insufficient drainage shown by increased mean transit time in cerebral magnetic resonance (MR) perfusion studies. CCSVI is strongly associated with multiple sclerosis (MS). This study evaluated the safety of CCSVI endovascular treatment and its influence on the clinical outcome of the associated MS. METHODS Sixty-five consecutive patients with CCSVI, subdivided by MS clinical course into 35 with relapsing remitting (RR), 20 with secondary progressive (SP), and 10 with primary progressive (PP) MS, underwent percutaneous transluminal angioplasty (PTA). Mean follow-up was 18 months. Vascular outcome measures were postoperative complications, venous pressure, and patency rate. Neurologic outcome measures were cognitive and motor function assessment, rate of MS relapse, rate of MR active positive-enhanced gadolinium MS lesions (Gad+), and quality of life (QOL) MS questionnaire. RESULTS Outpatient endovascular treatment of CCSVI was feasible, with a minor and negligible complication rate. Postoperative venous pressure was significantly lower in the IJVs and AZY (P < .001). The risk of restenosis was higher in the IJVs compared with the AZY (patency rate: IJV, 53%; AZY, 96%; odds ratio, 16; 95% confidence interval, 3.5-72.5; P < .0001). CCSVI endovascular treatment significantly improved MS clinical outcome measures, especially in the RR group: the rate of relapse-free patients changed from 27% to 50% postoperatively (P < .001) and of MR Gad+ lesions from 50% to 12% (P < .0001). The Multiple Sclerosis Functional Composite at 1 year improved significantly in RR patients (P < .008) but not in PP or SP. Physical QOL improved significantly in RR (P < .01) and in PP patients (P < .03), with a positive trend in SP (P < .08). Mental QOL showed significant improvement in RR (P < .003) and in PP (P < .01), but not in SP. CONCLUSIONS PTA of venous strictures in patients with CCSVI is safe, and especially in patients with RR, the clinical course positively influenced clinical and QOL parameters of the associated MS compared with the preoperative assessment. Restenosis rates are elevated in the IJVs but very promising in the AZY, suggesting the need to improve endovascular techniques in the former. The results of this pilot study warrant a subsequent randomized control study.

The value of cerebral Doppler venous haemodynamics in the assessment of multiple sclerosis

Iron stores in the white and deep grey matter in course of multiple sclerosis (MS) have never been explained and could be related to abnormalities in venous drainage, but this possibility has never before been investigated. From an initial cohort of 320 subjects, after application of exclusion criteria, we selected 109 patients affected by MS, and 177 controls respectively composed by age- and sex-matched, healthy aged, and patients affected by other neurological diseases. They blindly underwent transcranial and extracranial Color-Doppler sonographic examination (TCCS-ECD), aimed at investigating five parameters related to normal cerebral venous outflow haemodynamics. Overall we analyzed 1430 TCSS-ECD parameters. In controls we found 861 normal parameters of cerebral venous return vs. 24 anomalous, whereas in MS 288 parameters were normal and 257 anomalous, respectively. Consequently, each of the considered Doppler haemodynamic parameters, when compared to revised McDonald criteria as a gold standard of MS diagnosis, showed separately a highly significant sensitivity and a noteworthy specificity. However, the detection >or=2 parameters in the same subject, never observed in controls, perfectly overlapped the diagnosis of MS (value, 95%CI: sensitivity 100%, 97-100; specificity 100%, 98-100; positive predictive value 100%, 97-100, negative predictive value 100%, 98-100; p<0.0001). Moreover, this study demonstrates a significant impairment of cerebral venous drainage in patients affected by MS, a mechanism potentially related to increased iron stores.

Anomalous venous blood flow and iron deposition in multiple sclerosis.

Multiple sclerosis (MS) is primarily an autoimmune disorder of unknown origin. This review focuses iron overload and oxidative stress as surrounding cause that leads to immunomodulation in chronic MS. Iron overload has been demonstrated in MS lesions, as a feature common with other neurodegenerative disorders. However, the recent description of chronic cerebrospinal venous insufficiency (CCSVI) associated to MS, with significant anomalies in cerebral venous outflow hemodynamics, permit to propose a parallel with chronic venous disorders (CVDs) in the mechanism of iron deposition. Abnormal cerebral venous reflux is peculiar to MS, and was not found in a miscellaneous of patients affected by other neurodegenerative disorders characterized by iron stores, such as Parkinsons, Alzheimers, amyotrophic lateral sclerosis. Several recently published studies support the hypothesis that MS progresses along the venous vasculature. The peculiarity of CCSVI-related cerebral venous blood flow disturbances, together with the histology of the perivenous spaces and recent findings from advanced magnetic resonance imaging techniques, support the hypothesis that iron deposits in MS are a consequence of altered cerebral venous return and chronic insufficient venous drainage.

Intracranial Venous Haemodynamics in Multiple Sclerosis

In multiple sclerosis (MS) plaques are known to be venocentric; in addition, MS lesions and peripheral venous disorders share a number of key features. To date, however, despite the anatomical relationship between MS lesions and the venous system, no information on the intracranial venous haemodynamics of MS is available. Eighty-nine consecutive MS patients (58 relapsing-remitting, 31 secondary progressive) matched with 60 controls underwent transcranial color-coded duplex sonography (TCCS). We assessed, in supine as well as in sitting positions, the direction of flow at the activation of the thoracic pump in the deep middle cerebral veins (dMCVs), and in the transverse sinus (TS). In the dMCVs, we also measured peak systolic velocity (PSV), peak diastolic velocity (PDV), as well as the resistance index (RI). Reflux/bidirectional flow rate was significantly higher in the MS population determining also significant differences in PDV, characterized by negative values (16.2+/-1 cm/sec in controls vs. -1.3 +/-2.6 cm/sec in MS, respectively, p<0.0001). Consequently, RI was dramatically increased in the MS group, affecting impedance of cerebral venous drainage (0.48+/-0.04 in controls vs. 1.1 +/-0.08 in MS, respectively p<0.0001). Therefore, the detection of reflux directed toward the subcortical grey matter was significantly associated to highest disability scores (p < 0.0001). Our study of MS patients demonstrated significant haemodynamic alterations detected in veins anatomically related to plaque disposition. Our findings should contribute towards understanding the role of altered venous flow and tissue drainage in the MS inflammatory chain, as well as in the neurodegenerative process.

Venous Collateral Circulation of the Extracranial Cerebrospinal Outflow Routes

A new nosologic vascular pattern that is defined by chronic cerebrospinal venous insufficiency (CCSVI) has been strongly associated with multiple sclerosis. The picture is characterized by significant obstacles of the main extracranial cerebrospinal veins, the jugular and the azygous system, and by the opening of substitute circles. The significance of collateral circle is still neglected. To the contrary, substitute circles are alternative pathways or vicarious venous shunts, which permit the drainage and prevent intracranial hypertension. In accordance with the pattern of obstruction, even the intracranial and the intrarachidian veins can also become substitute circles; they permit redirection of the deviated flow, piping the blood toward available venous segments outside the central nervous system. We review the complex gross and radiological anatomy of collateral circulation found activated by the means of EchoColor-Doppler and selective venography in the event of CCSVI, focusing particularly on the suboccipital cavernous sinus (SCS), the condylar venous system, the pterygoid plexus, the thyroid veins, and the emiazygous-lumbar venous anastomosis with the left renal vein.

The chronic cerebrospinal venous insufficiency syndrome

Chronic cerebrospinal venous insufficiency (CCSVI) is a syndrome characterized by stenosies of the internal jugular and/or azygous veins (IJVs-AZ) with opening of collaterals and insufficient drainage proved by reduced cerebral blood flow and increased mean transit time in cerebral MRI perfusional study. The present review is aimed to give a comprehensive overview of the actual status of the art of the diagnosis and treatment of this condition. As far as the origin of venous narrowing is concerned, phlebographic studies of the IJVs and AZ systems demonstrated that venous stenoses were likely to be truncular venous malformations; mostly, they are intraluminal defects such as malformed valve, septa webs. CCSVI condition has been found to be strongly associated with multiple sclerosis (MS), a disabling neurodegenerative and demyelinating disease considered autoimmune in nature. In several epidemiological observations performed at different latitudes on patients with different genetic backgrounds, the prevalence of CCSVI in MS ranges from 56% to 100%. To the contrary, by using venous MR and/or different Doppler protocols, CCSVI was not detected with the same prevalence. Two pilot studies demonstrated the safety and feasibility in Day Surgery of the endovascular treatment of CCSVI by means of balloon angioplasty (PTA). It determines a significant reduction of postoperative venous pressure. Restenosis rate was found out elevated in the IJVs, but negligible in the AZ. However, PTA seems to positively influence clinical and QoL parameters of the associated MS and warrants further randomized control trials.

Venous Angioplasty in Patients with Multiple Sclerosis: Results of a Pilot Study

OBJECTIVES Chronic cerebrospinal venous insufficiency (CCSVI) is associated with multiple sclerosis (MS). The objective of the study was to see if percutaneous transluminal angioplasty (PTA) of duplex-detected lesions, of the internal jugular and/or azygous veins, was safe, burdened by a significant restenosis rate, and whether there was any evidence that treatment reduced MS disease activity. DESIGN This was a case-control study. MATERIALS We studied 15 patients with relapsing-remitting MS and duplex-detected CCSVI. METHODS Eight patients had PTA in addition to medical therapy (immediate treatment group (ITG)), whereas seven had treatment with PTA after 6 months of medical therapy alone (delayed treatment group (DTG)). RESULTS No adverse events occurred. At 1 year, there was a restenosis rate of 27%. Overall, PTA was followed by a significant improvement in functional score compared with baseline (p < 0.02). The annualised relapse rate was 0.12% in the ITG compared with 0.66% in the DTG (p = NS). Magnetic resonance imaging (MRI) blindly demonstrates a trend for fewer T2 lesions in the ITG (p = 0.081), corresponding to a 10% decrease in the ITG compared with a 23% increase in the DTG over the first 6 months of the study. CONCLUSIONS This study further confirms the safety of PTA treatment in patients with CCSVI associated with MS. The results, despite the significant rate of restenosis, are encouraging and warrant a larger multicentre double-blinded, randomised study.

Early oral feeding after colorectal resection: a randomized controlled study

Background:  Nasogastric (NG) intubation is widely used following elective abdominal operations although it is associated with morbidity and discomfort. The present study is a randomised controlled trial on the effect of early oral feeding without NG decompression following elective colorectal resection for cancer.