Mitochondrial Aconitase Enzymatic Activity: A Potential Long-Term Survival Biomarker in the Blood of ALS Patients

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a multisystemic, progressive, neurodegenerative disorder. Despite it being generally fatal within a period of 2-4 years, it is highly heterogeneous; as a result, survival periods may vary greatly among individual patients. Biomarkers can serve as tools for diagnosis, prognosis, indicators of therapeutic response, and future therapeutics. Free-radical-dependent mitochondrial damage is believed to play a crucial role in neurodegeneration in ALS. Mitochondrial aconitase, which is also known as aconitase 2 (Aco2), is a key Krebs cycle enzyme and is involved in the regulation of cellular metabolism and iron homeostasis. Aco2 is very sensitive to oxidative inactivation and can aggregate and accumulate in the mitochondrial matrix, causing mitochondrial dysfunction. Loss of Aco2 activity may therefore reflect increased levels of mitochondrial dysfunction due to oxidative damage and could be relevant to ALS pathogenesis. The aim of our study was to confirm changes in mitochondrial aconitase activity in peripheral blood and to determine whether such changes are dependent on, or independent of, the patient's condition and to propose the feasibility of using them as possible valid biomarkers to quantify the progression of the disease and as a predictor of individual prognosis in ALS.

METHODS

We measured the Aco2 enzymatic activity in the platelets of blood samples taken from 22 controls and 26 ALS patients at different stages of disease development. We then correlated antioxidant activity with clinical and prognostic variables.

RESULTS

Aco2 activity was significantly lower in the 26 ALS patients than in the 22 controls (p < 0.05). Patients with higher levels of Aco2 activity survived longer than those with lower levels (p < 0.05). Aco2 activity was also higher in patients with earlier onset (p < 0.05) and in those with predominantly upper motor neuron signs.

CONCLUSIONS

Aco2 activity seems to be an independent factor that could be used in the long-term survival prognosis of ALS. Our findings suggest that blood Aco2 could be a leading candidate for use as a biomarker to improve prognosis. More studies are needed to confirm these results.

Type XIX collagen: a promising biomarker from the basement membranes

Among collagen members in the collagen superfamily, type XIX collagen has raised increasing interest in relation to its structural and biological roles. Type XIX collagen is a Fibril-Associated Collagen with Interrupted Triple helices member, one main subclass of collagens in this superfamily. This collagen contains a triple helix composed of three polypeptide segments aligned in parallel and it is associated with the basement membrane zone in different tissues. The molecular structure of type XIX collagen consists of five collagenous domains, COL1 to COL5, interrupted by six non-collagenous domains, NC1 to NC6. The most relevant domain by which this collagen exerts its biological roles is NC1 domain that can be cleavage enzymatically to release matricryptins, exerting anti-tumor and anti-angiogenic effect in murine and human models of cancer. Under physiological conditions, type XIX collagen expression decreases after birth in different tissues although it is necessary to keep its basal levels, mainly in skeletal muscle and hippocampal and telencephalic interneurons in brain. Notwithstanding, in amyotrophic lateral sclerosis, altered transcript expression levels show a novel biological effect of this collagen beyond its structural role in basement membranes and its anti-tumor and anti-angiogenic properties. Type XIX collagen can exert a compensatory effect to ameliorate the disease progression under neurodegenerative conditions specific to amyotrophic lateral sclerosis in transgenic SOD1G93A mice and amyotrophic lateral sclerosis patients. This novel biological role highlights its nature as prognostic biomarker of disease progression in and as promising therapeutic target, paving the way to a more precise prognosis of amyotrophic lateral sclerosis.

Collagen XIX Alpha 1 Improves Prognosis in Amyotrophic Lateral Sclerosis

The identification of more reliable diagnostic or prognostic biomarkers in age-related neurodegenerative diseases, such as Amyotrophic Lateral Sclerosis (ALS), is urgently needed. The objective in this study was to identify more reliable prognostic biomarkers of ALS mirroring neurodegeneration that could be of help in clinical trials. A total of 268 participants from three cohorts were included in this study. The muscle and blood cohorts were analyzed in two cross-sectional studies, while the serial blood cohort was analyzed in a longitudinal study at 6-monthly intervals. Fifteen target genes and fourteen proteins involved in muscle physiology and differentiation, metabolic processes and neuromuscular junction dismantlement were studied in the three cohorts. In the muscle biopsy cohort, the risk for a higher mortality in an ALS patient that showed high Collagen type XIX, alpha 1 (COL19A1) protein levels and a fast progression of the disease was 70.5% (P < 0.05), while in the blood cohort, this risk was 20% (P < 0.01). In the serial blood cohort, the linear mixed model analysis showed a significant association between increasing COL19A1 gene levels along disease progression and a faster progression during the follow-up period of 24 months (P < 0.05). Additionally, higher COL19A1 levels and a faster progression increased 17.9% the mortality risk (P < 0.01). We provide new evidence that COL19A1 can be considered a prognostic biomarker that could help the selection of homogeneous groups of patients for upcoming clinical trial and may be pointed out as a promising therapeutic target in ALS.

Mitochondrial complex enzyme activities and cytochrome C expression changes in multiple sclerosis

Blood platelets have been widely proposed as biomarkers in studies of mitochondrial function and aging-related and neurodegenerative diseases. Defects in mitochondrial function were found not only in the substantia nigra of Parkinson's disease patients but also in their blood platelets. Similarly, it has also been described in the blood platelet mitochondria of Alzheimer's disease patients. To study mitochondrial aerobic metabolism function and protein expression in platelets of multiple sclerosis (MS) patients and control subjects, mitochondrial aconitase, mitochondrial superoxide dismutases 1 and 2 (SOD1 and SOD2), and respiratory complex enzyme activities in platelets of MS patients and control subjects were determined. Likewise, mitochondrial lipid peroxidation and mitochondrial SOD1 and cytochrome c expressions were investigated. Mitochondrial aconitase activity was higher in MS patients than in controls (P < 0.05). A significant increase on all respiratory complex activities in MS patients was observed (P < 0.05). Mitochondrial lipid peroxidation was significantly higher in MS patients than in controls (P < 0.05). Significant changes of cytochrome c and mitochondrial SOD1 expressions were detected (P < 0.05), with a decrease of 44 ± 5 % and an increase of 46 ± 6 %, respectively. Our study reveals that significant changes in mitochondrial aerobic metabolism function and mitochondrial SOD1 and cytochrome c expressions are produced in platelets of MS patients.

Analysis of the C9orf72 gene in patients with amyotrophic lateral sclerosis in Spain and different populations worldwide

A hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72) can cause amyotrophic lateral sclerosis (ALS) and/or frontotemporal dementia (FTD). We assessed its frequency in 781 sporadic ALS (sALS) and 155 familial ALS (fALS) cases, and in 248 Spanish controls. We tested the presence of the reported founder haplotype among mutation carriers and in 171 Ceph Europeans from Utah (CEU), 170 Yoruba Africans, 81 Han Chinese, and 85 Japanese subjects. The C9orf72 expansion was present in 27.1% of fALS and 3.2% of sALS. Mutation carriers showed lower age at onset (P = 0.04), shorter survival (P = 0.02), greater co-occurrence of FTD (P = 8.2 × 10(-5)), and more family history of ALS (P = 1.4 × 10(-20)), than noncarriers. No association between alleles within the normal range and the risk of ALS was found (P = 0.12). All 61 of the mutation carriers were tested and a patient carrying 28 hexanucleotide repeats presented with the founder haplotype. This haplotype was found in 5.6% Yoruba Africans, 8.9% CEU, 3.9% Japanese, and 1.6% Han Chinese chromosomes.

Monitoring systemic oxidative stress in an animal model of amyotrophic lateral sclerosis

A mutant form of the ubiquitous copper/zinc superoxide dismutase (SOD1) protein has been found in some patients with amyotrophic lateral sclerosis (ALS). We monitored oxidative stress in an animal model of ALS, the SOD(G93A) mouse, which develops a disease similar to ALS with an accelerated course. The aim of this work was to show that ALS damages several organs and tissues, from an oxidative stress point of view. We measured lipid and protein oxidative damage in different tissue homogenates of SOD(G93A) mice. The biomarkers that we analyzed were malondialdehyde + 4-hydroxyalkenal (MDA + 4-HDA) and carbonyls, respectively. The spinal cord and brain of SOD(G93A) mice showed increased lipid peroxidation after 100 or 130 days compared to age-matched littermate controls. The CNS was most affected, but lipid peroxidation was also detected in the skeletal muscle and liver on day 130. No changes were observed in protein carbonylation in the homogenates. Our results are consistent with a multisystem etiology of ALS and suggest that oxidative stress may play a primary role in ALS pathogenesis. Thus, oxidative stress represents a potential biomarker that might be useful in developing new therapeutic strategies for ALS.

Severe infantile-onset cardiomyopathy associated with a homozygous deletion in desmin

Desminopathy is a genetically heterogeneous disorder with autosomal dominant pattern of inheritance in most affected families; the age of disease onset is on average 30 years. We studied a patient with a history of recurrent episodes of syncope from infancy who later developed second-degree AV block and restrictive cardiomyopathy; she subsequently suffered several episodes of ventricular tachyarrhythmia requiring implantation of bicameral defibrillator. Neurological examination revealed rapidly progressive bilateral facial weakness, winging of the scapulae, symmetric weakness and atrophy of the trunk muscles, shoulder girdle and distal muscles of both upper and lower extremities. Muscle biopsy demonstrated signs of myofibrillar myopathy with prominent subsarcolemmal desmin-reactive aggregates. Molecular analysis identified a homozygous deletion in DES resulting in a predicted in-frame obliteration of seven amino acids (p.R173_E179del) in the 1B domain of desmin. We describe the youngest known desminopathy patient with severe cardiomyopathy and aggressive course leading to the devastation of cardiac, skeletal and smooth musculature at an early age.

[Pure lower motoneurone syndrome in a series of six patients]

INTRODUCTION

Lower motoneurone syndromes (SMNI) have been defined by their clinical pattern, anomalies in nerve conduction and the presence of antiglycolipid antibodies. The possible response to immunotherapy is another characteristic which makes these syndromes interesting.

PATIENTS AND METHODS

We studied the clinical and electrophysiological data, clinical progress and response to treatment of a series of six patients, with a pure lower motoneurone syndrome, with a follow up period of between 5 and 13 years.

CONCLUSIONS

The clinical phenotype of our patients was: male, middle aged, the clinical topography showed only lower motoneurone involvement, predominantly or exclusively limited to the upper limbs, asymmetrical, distal rather than proximal, with a chronic course progressing initially but later becoming stable. From the electrophysiological point of view some of our cases were of SMNI. In these the conduction block was not permanent although there were signs of axon loss and multifocal demyelination. Response to treatment with intravenous immunoglobulins was seen in patients with anti GMI antibodies of IgM type and recent signs of clinical deterioration, whether there were conduction blocks present or not. In the cases which responded to this treatment there was tolerance and dependence following repeated transfusions of IV IgG.

[Neurological alterations related to Crohn's disease]

INTRODUCTION

The incidence of alterations of the central and/or peripheral nervous system in a patient with Crohn s disease (EC) is 33.2%. Casual association may occur in 19.3% of the cases. The disorder of the nervous system may precede the diagnosis of EC.

DEVELOPMENT

We review the main neurological complications of EC. The predominant cerebral vascular pathology is arterial although cases of venous thrombosis have been reported. One of the mechanisms involved is the state of hypercoagulability secondary to thrombocytosis and increase in the factors V, V111 and fibrinogen. In other cases there was confirmation of the presence of antiphospholipid antibodies and lupus anticoagulant, and therefore of an autoimmune mechanisms being involved. Other neurological features include peripheral neuropathy (axonal, demyelinating and autonomic), myopathies, pseudotumor cerebri, papilloedema, psychiatric disorders (anxiety, phobias, depression) and association with syndromes such as multiple sclerosis, Cogan s syndrome, Melkersson Rosenthal syndrome, connective tissue disorders and vasculitis.

CONCLUSION

As well as hypercoagulability being one of the pathogenic mechanisms of cerebral ischaemia, there is alteration of humoral and cellular immunity in patients with EC. This justifies this and other neurological manifestations, and explains its association with other immunity disorders.

[Sjögren's syndrome and multiple sclerosis]

INTRODUCTION

Multiple sclerosis (MS) usually follows a relapsing-remitting course and attacks multiple areas of the central nervous system (CNS). Certain rheumatic diseases, including Sjögren's syndrome (SS), can present with a similar clinical picture.

RESULTS

Two patients out 67 of 100 with MS exhibited xerophthalmia and xerostomia and positive Ro antibodies, thus fulfilling 55 diagnostic criteria. Case 1. A 62-year-old woman developed several episodes of numbress and weakness in her left extremity and ataxia. MRI demonstrated a high-intensity areas in periventricular white matter. Initial laboratory studies failure to demonstrate antinuclear antibodies. Xerostomia and xerophthalmia were apparent. Follow-up laboratory examinations showed elevated ANA, Anti-SSA and anti-SSB. Case 2. A 58-year-old woman was diagnosed as having MS at the age of 53 years. Several high-signal foci on MRI were demonstrated in the white matter. Initial serum findings including autoantibodies were unremarkable. Sicca syndrome was present. Laboratory investigations included elevated anti-SSA, anti-SSARo52 and ANA while anti-SSB was within normal limits.

DISCUSSION

Primary SS is a chronic autoimmune inflammatory disease of unknown etiology. The CNS symptoms are present in 20-25% of the patients with SS. Some patients have a relapsing-remitting course mimicking MS. Focal brain lesions in SS can occur in the cerebral white matter. The features of our patients sufficiently mimicked those of MS and this disorder was the diagnosis in each patient at the time of initial evaluation. SS should be considered in th

[Peripheral neuropathy associated with intestinal inflammatory disease]

The association of outlying peripheral neuropathy and inflammatory bowel disease is a rare fact leaving aside factors like the deficit of intestinal absorption of vitamins or the neurotoxicity of drugs employed for the treatment of the inflammatory bowel disease. We presented a series of four patients with this association, to whom a retrospective study was carried out. In all cases polineuropathy followed a course parallel to the inflammatory bowel disease, being acute and reversible in two cases. The polyneuropathy could be attributed to a deficit of vitamin B12 in one case and to metronidazole neurotoxicity in the other; in the remaining two cases the polineuropathy was chronic and no etiological factor could be found except for the own activity of the inflammatory bowel disease. We think that the neuropathy can represent a rare extraintestinal manifestation of the illness with a common autoimmune pathogenic mechanism. In one of our cases, the nerve biopsy demonstrated an axonal neuropathy with an alteration of the epineural vessels which showed a healed aspect.

[Steroid treatment of acute psychosis associated with multiple sclerosis]]

INTRODUCTION

Psychiatric disorders are common in patients suffering from multiple sclerosis (MS). Psychosis is a rare complication in this condition. We present two patients with MS and psychosis.

CLINICAL CASES

Case 1. A 45-year-old man was admitted to the hospital because an acute psychosis. The diagnosis of clinical definitive MS was made two years before. Cranial magnetic resonance imaging (MRI) and single positron emission computerized tomography (SPECT) showed lesions in the left temporal lobe. He was treated with a 3-day course of high-dose corticosteroid and neuroleptic. The patient's status gradually improved within the following weeks. Case 2. A 41-year-old man with MS was hospitalized in a Psychiatric Department for acute psychosis. He was treated with high-dose of neuroleptic. Thereafter two remissions and relapses of MS have occurred. In 1998, the patient was evaluated in the Service of Psychiatric for new paranoid acute psychosis.

CONCLUSIONS

Psychosis is not a prominent feature of the disease, occurring in 5% of cases. The relationship between lesions of the central nervous system and psychiatric illness has not been established although some reports have implicated the temporal lobe. The propensity of steroids to exacerbate psychosis usually argues against this option, but steroids could theoretically improve psychosis related to acute demyelination.

[Peripheral nervous system neurotoxicity secondary to chemotherapy treatment]

Peripheral neurotoxicity is a crucial side effect of chemotherapeutic agents. It is the only situation where there is no preventive treatment. Neuromuscular toxicity has become the major dose limiting side effect for many chemotherapeutic agents. The iatrogenic toxic neuropathy is a growing neurologic problem, as cancer patients are beign treated with increasing doses of chemotherapy drugs. Major advances in cancer treatment have resulted from the use of drug combinations; for some combinations this raises the possibility of sinergistic neurotoxicity. The following report reviews the SNP toxicities encountered with cisplatin, vincristine, taxanes and others, and methods to minimize the deleterious effect of chemotherapeutic agents.

[Acute transverse myelitis secondary to hepatitis B vaccination]

INTRODUCTION

Acute transverse myelitis is an inflammatory disorder. The pathogenesis is unclear, but the probable mechanism involves an autoimmune phenomenon. Possible causes included multiple sclerosis and parainfectious and postvaccinal events. Myelitis has rarely been reported secondary to vaccinations including hepatitis B. We present a case of acute myelitis, which seems secondary to the administration of the hepatitis B vaccine.

CLINICAL CASE

A 15-years-old female presented with progressive numbness of the right arm and leg, with right leg weakness. Symptom began one week after receiving the first dose of the hepatitis B vaccine. Spinal cord magnetic resonance (MR) revealed a diffuse increased signal extending from C6 to D2. Cerebral MR and cerebrospinal fluid were normal. She was treated with high doses of methylprednisolone with a complete recovery of neurological functional. Repeat medullar cord MR was normal. There was no relapse during a four years follow up.

CONCLUSIONS

Potential causal relationship between vaccination against hepatitis B and multiple sclerosis was brought to the attention and to public debate. However, no conclusive association could be made between vaccination and demyelination. In the clinical setting, the distinction between a first episode of multiple sclerosis or postvaccinal myelitis depends upon subsequent course.

Reversible peripheral neuropathy induced by a single administration of high-dose paclitaxel

Peripheral neuropathy (PN) is the main side effect with cycles of paclitaxel at standard doses (175 mg/m2 for 21 days). Administration of a single high-dose paclitaxel (HDP) is a novel approach for the treatment of cancer. We have prospectively measured neurotoxicity induced by HDP during a phase I trial. Nineteen patients were treated with escalating doses of paclitaxel by 24-hour infusion. In our study, PN induced by HDP was moderate, reversible, and not dose limiting. Severe PN was seen in patients who had received previous neurotoxic chemotherapy, and caution on the administration of HDP in this setting is warranted.

[Response to treatment of chronic daily headache with analgesic abuse]

The overuse of analgesics in patients with chronic daily headache (CDH) perpetuates and worsens the headache. The aim of this study was to evaluate the clinical response to withdrawal of analgesics and to preventive treatment in a group of patients with CDH. Eighty-four patients who were taking daily symptomatic medications, and suffering from CDH were studied. Treatment consisted of withdrawal of daily symptomatic medications and prophylactic therapy. Improvement was considered when intensity and frequency of the headache were reduced more than 50%. After a 2-15 months follow-up, 57 of the 76 patients that continued in the study had improved. From these, 98% had reduced the consumption of analgesics below the figures considered as abuse and a 94% took the prophylactic medications correctly. After giving up the preventive treatment, 26% of the patient presented CDH and the 60% overuse again of analgesics. These results show that withdrawal of analgesics is necessary for improvement in patients with CDH, but the possibility of relapses is elevated. We think that there are other factors implicated in the development of CDH. We therefore believe that in order to avoid the relapses this group of patients need follow-up and preventive treatments during long periods of time.

[Mandibular neuropathy due to infiltration of the Gasser ganglion]

INTRODUCTION

The numb chin syndrome is characterized by oral and facial numbness restricted to the distribution of the mental nerve. This uncommon neuropathy has been described in association with a number conditions including malignant disease even in the patients no known to have cancer. Numb chin syndrome may be caused by metastatic involvement of the mental nerve, by involvement of the proximal mandibular root at the base of the skull or by intracranial leptomeningeal spread.

CLINICAL CASE/DISCUSSION

We described a case of neuropathy of the chin as the initial symptom of the breast cancer. We suggested that the lesion was in the trigeminal ganglion based on enlargement and gadolinium enhancement of the trigeminal ganglia on MRI. A mental neuropathy should initiate a search for cancer that includes MRI of the head.

[Clinical features of daily chronic headache]

INTRODUCTION

Although the International Headache Society considers chronic tension headache to be a chronic headache, patients with daily chronic headache may have pain which is not only due to tension but also has migrainous features.

OBJECTIVE

To evaluate the clinical differences and abuse of drugs in a group of patients with chronic daily headache who were consecutively evaluated in the Neurology Clinic.

MATERIAL AND METHODS

We consider the patients to have daily chronic headache when they have had pain at least 6 days a week for the past 6 months. Using this criterion, we studied 112 patients, of whom 90 (80.4%) were women and 22 (19.6%) men. Results. Sixty nine (61.6%) had transformed migraine and 43 (38.4%) tension headache. There were no differences in their current ages but the age of onset of the headaches varied (p = 0.000,t). Unilateral pain, trigger factors and a family history were more frequent in the cases of transformed migraine. Eighty four patients (75%) abused analgesics. Although we found different pain intensities (p = 0.000, chi 2) there was no difference in the weekly consumption of analgesics (p = 0.64, t) in the mg/week of ergotamine (p = 0.96, t) nor in absence from work between the two types of headache.

CONCLUSIONS

In spite of clinical differences between transformed migraine and tension headache, which may help diagnosis, in our series abuse of analgesics (including ergotamine) was a common characteristic.

[Isolated vasculitis of the peripheral nervous system]

We present a patient with a subacute asymmetrical sensorimotor polyneuropathy. The pathological features were predominantly loss of nerve fibers, axonal degeneration and healed vasculitis. The epineural vessels were involved, while endoneurial capillaires were preserved. Muscle biopsy revealed neurogenic features with normal blood vessels. After three years, motor and sensory function was almost normal, without any specific treatment. No abnormal findings suggesting collagen diseases or other underlying immunological disorders were obtained by various laboratory tests. In conclusion, the present case strongly suggests that the vasculitis was confined to the peripheral nerves.

[Peripheral neuropathy and mixed cryoglobulinemia: clinical, neuro- physiological and pathological signs in a group of 12 patients]

This retrospective study involved a series of 12 patients with peripheral neuropathy and mixed type III cryoglobulinemia. The predominating symptoms were sensory. In patients with essential cryoglobulinemia, neuropathy most often presented as multiple mononeuropathy, while polyneuropathic forms were most common among those with secondary cryoglobulinemia. The absence of cryosensitivity was evident in secondary forms. Both neurophysiological and morphological examination revealed a predominance of axonal neuropathy. Two cases of demyelinating neuropathy were found among those with secondary cryoglobulinemia associated with monoclonal gammopathy. Although the vascular lesion was clearly demonstrable in muscle and skin tissue, this was not so in the nervous system.