Jacobs Journal of Neurology and Neuroscience

The Multi-Target Therapy Approach to Stop Multiple Sclerosis Progression

*Enrique De Font-Réaulx
Department Of Neurology, ABC Medical Center, Mexico

*Corresponding Author:
Enrique De Font-Réaulx
Department Of Neurology, ABC Medical Center, Mexico
Email:defontreaulx@hotmail.com

Published on: 2018-05-19

Abstract

Background: Multiple Sclerosis (MS) is one of the neurodegenerative diseases that have caught the most attention in the last 4 decades. Although there are several treatments to stop progression, none of them has been designed specifically for this disease until now. Each of these treatments has only one action mechanism and is an immunomodulator or immunosupressor with varying results with frequent collateral effects. Here is described the first oral Multi-Target Treatment (MTT) specifically designed to halt disease progression. The MTT consists of four substances that have a synergistic effect in controlling the most important known mechanisms of disease progression: aberrant apoptosis, oxidative damage, mitochondrial degeneration, caspase activation, syncytin-mediated neuroinflammation, and Mitogen-Activated Protein-Kinases activation.

Results: 33 patients with MS were treated with the MTT only, age 19 to 60 years (mean 37.12 years, SD +/-12.05), 19 female (57.6%), 14 male (42.4%). The basal Expanded Disability Status Scale (EDSS) score was 0-8 (mean 2.43, SD +/- 2.47). Maximum follow-up period was 94 months, mean 40.7 months. There were 13 patients (39.39 %) that improved their basal EDSS score and 17 patients (51.51%) had no increase in their EDSS score during the follow up period. Overall, 30 patients (90.9%) remained with the same or better EDSS score during the follow up. The mean EDSS at 64 months of follow up remained at 2.7 (n=11). The EDSS was worse in 3 patients (9 %). In the subgroup where progressive variants were excluded (n=26), there were 12 patients (46.2%) that improved their basal EDSS score and 14 patients (53.8%) had no increase in their EDSS score. None of the patients in this subgroup had a worse EDSS score in the follow up period. The mean basal EDSS was 0 to 8 (mean 1.9), and at 64 month of follow up was 0.8 (n=7) versus an expected deterioration in EDSS of 3.5 points at 64 months, as calculated by the progression index established in historic MS patients. At 76 months of follow up, the mean EDSS score was 0.25 (n=4). No adverse effects were observed while using the MTT.

Conclusions: The Multi-Target Therapy here described is a promising treatment that may stop the progression of MS.

Keywords

Multi-Target Therapy, Multiple Sclerosis, Disease modifying treatment, Clinical stabilization, Apoptosis, Neuroprotection, Neurodegeneration

Background

Multiple sclerosis (MS) is a chronic, progressive degenerative disease affecting the central nervous system (CNS) [1], involving several autoimmune and inflammatory etiologic mechanisms still under study. The final effect is the damage to the myelin of the CNS [2,3] with varying affection to various functions.

It affects approximately twice the number of women than men [2]. The diagnosis is clinical accompanied with supporting cranial Magnetic Resonance Imaging (MRI) results and lumbar puncture results. The age range with the maximum incidence is 20 to 45 years, with occasional cases before and after this range [4].

It is estimated that there are between 250,000 to 350,000 persons affected by MS in USA [5]. Half of them will need assistance to walk within 15 years from having started with the disease [6].

The cause is still under research. It is currently accepted that some environmental or metabolic factors or viral infectious stimuli may trigger the disease. It has also been postulated with growing evidence, that the activation of the Human Endogenous Retro-Virus (HERV) may play an important role in the beginning and progression of the disease, causing syncytin-mediated neuroinflammation [7].

Current Disease-Modifying Therapies

The objective of the disease-modifying agents is to decrease the duration of the relapses, reduce their frequency and improve the symptoms [4]. At present, there is no cure for MS.

The most used disease-modifying therapies are Beta Interferons (BI), Glatiramer Acetate (GA), mitoxantrone, natalizumab and fingolimod. All of them attenuate the immunological response as a collateral effect of their mechanism of action, but none of them are designed to avoid the targeting of the myelin by the immune system. They have shown a varying efficacy on the progression of MS, with reduction of the number of relapses [8-10, 16-22], and they reduce cranial MRI-detected inflammatory lesions [11-13], but there is no precise correlation between the number of MRI-detected injuries and the clinical condition of the patient. Although a lower number of relapses are reported with the use of these treatments, its long-term efficacy is questioned. None of them halts the progression of MS completely, and they usually have frequent and even dangerous collateral effects. Their undesirable effects of BI include severe liver damage, depression, dysthyroidism and leukopenia [4], fever, chills, general malaise, muscle ache and fatigue [14]. It may heighten symptoms such as spasticity, and other undesirable effect is the reaction on the injection site [14], peripheral neuropathy [15], reactions in the injection site, itchiness and rash, flu symptoms, thoracic pain, headache and heat sensation [16], vomit (18%–85%), alopecia (33%–61%), amenorrhea (8%–53%), urinary infections (6%–32%) and upper respiratory tract infections (4%–53%), leukopenia in 10% to 19% of patients [17]. The use of mitoxantrone may cause serious undesirable effects, such as cardiotoxicity, myelosuppression and leukemia [17].

Due to the use of natalizumab, there is a risk of developing progressive multifocal leukoencephalopathy, which may cause severe disabilities or death [18]. This risk increases in relation to the duration of natalizumab’s use. Anaphylaxis and severe infections have also been reported due to its use [19]. The collateral effects of the use of fingolimod include headache, elevated transaminases, influenza infections, diarrhea, lower-back pain, and cough. The heart rate must be monitored due to the risk of bradycardia in the first 6 hours of administering fingolimod. Two patients died in one of the clinical trials of the use of fingolimod due to herpes family viral infections [20].

New Potential Drugs under Investigation

At present, all drugs approved for the treatment of MS had been designed or adopted to modify the immunological function, but none of them prevents or mitigates the most important known mechanisms involved in MS progression or the targeting of the myelin by the immune system, as previously exposed in the mechanism of action of the approved drugs for MS treatment. The potential drugs being developed for the treatment of MS also have this conceptual deficiency. The principal potential drugs are: laquinimod is a synthetic small-molecule, anti-inflammatory agent; teriflunomide is an immune modulator; BG12 (dimethyl fumarate is an immune modulator; daclizumab is a CD25-targeted humanized monoclonal antibody; alemtuzumab is a CD52-targeted humanized monoclonal antibody, initially designed for the treatment of B-cell chronic lymphocytic leukemia; rituximab is a CD20-targeted chimeric murine/ human monoclonal antibody, initially designed for treatment of non-Hodgkin’s lymphoma; ocrelizumab is a CD20-targeted humanized monoclonal antibody [8].

Previously Ignored Therapeutic Targets

Syncytin-Mediated Neuroinflammation

Endogenization is a frequent event, as between 8 and 11% of currently studies of mammal genomes correspond to sequences with retroviral elements [23]. These genes are called Human Endogenous Retro-Virus (HERV). These are not only passive components of the genome, but are active, performing different functions such as HERV derived proteins syncytin-1 and 2, which are essential for differentiation in placental development [24,25]. It has been shown that HERV have an active participation in various diseases, such as cancer, autoimmune diseases, and neurodegeneration [23].

The most studied family is HERV-W. Two important findings stand out regarding this HERV family: the discovery of the Retrovirus Associated with MS (MSRV), present in leptomeningeal cells of patients with MS [26], and the discovery that syncytin-1 is codified by the gene env of HERVWE1, an incompetent replication element of HERV-W located in human chromosome 7q21-22 [27,28]. It has inactivating mutations in genes gag and pol and is incapable of producing viral particles. For its transcription, only locus ERVW-1 is fully transcribed in an mRNA env, which can be transcribed in a complete protein: syncytin-1 [29]. In addition to syncytin-1 being responsible for the implantation of the placenta of the human syncytiotrophoblast, syncytin-1 has other important functions, such as the potent regulatory transcriptional properties of Long-Term Repeats (LTR) and the possible role of the expression of HERV-Wenv in the suppression of the maternal immune response against the fetus.

Proteins MSRVenv and syncytin-1 share several biological characteristics and are potentially pathogenic. Both have superantigenic and proinflammatory properties [30] and have shown to cause neurotoxic effects in vitro in transgenic animal models [7,31]. These proteins may cause neuroinflammation, neurodegeneration, alterations in the immune system and stress response; it has been suggested that both act as co-factors, triggering the immunopathogenesis of MS [30]. In a clinical trial with MS patients, MSRV was found circulating in 100% of patients with active MS and 33% of patients with MS in remission phase [32]. In lesions of patients with MS there are high levels of transcription of MSRV/HERV-W, increased from 20 to 25 times (p=0.006). Through immunohistochemistry, it is not possible to detect the protein HERV-Wenv in the brains of healthy controls, but it is highly expressed in MS lesions, and this is correlated with the extension of active demyelination and inflammation. In the borders of MS lesions, the presence of HERV-W was found using immunohistochemistry, in microglia and in astrocytes, while in the center of the lesions, there was presence of HERV-W in hypertrophic astrocytes [33]. It has been demonstrated that some proinflammatory cytokines such as TNFα, IL-6 and interferon-γ are over produced in response to MSRV/HERV-Wenv by cells of patients with MS, and this is correlated with the severity of the disease [30,34], establishing a physiopathological amplification feedback.

In spite of the wide and growing evidence of there being an active and potent physiopathological relation between neurodegenerative diseases (NDD) such as MS and the expression of HERV-related genes, none of the treatments approved or in trial for control of progression of NDDs in general and MS in particular had included this therapeutic target. We previously described the treatment of NDDs, including MS, through a MTT, which, among other substances, includes ferulic acid, which is a potent inhibitor of the effects of syncytin in vivo [5]. In this article, we describe the long-term results of the treatment of patients with MS with only the use of this MTT.

Mitogen-Activated Protein-Kinases

The Mitogen-Activated Protein Kinase (MAPK) family, are serine-threonine kinases that mediate intracellular signaling that includes ERK1/2, JNK/SAPK, p38 and ERK5. Is involved in the survival, proliferation and differentiation of nervous cells. Some of the MAPKs promote the differentiation towards the neuron lineage, others towards the glial one. The MAPKs are also involved in apoptosis and may therefore, play a role in neurodegeneration [36]. The activation of the signaling network of MAPK and mTOR (mammalian target of rapamycin) is associated with cadmium-induced neuronal apoptosis. These results strongly suggest that inhibitors of MAPK and mTOR may have a potential for prevention of cadmium-induced neurodegeneration [37]. The JNK and p38 signaling pathway are activated by proinflammatory cytokines such as TNF-α e interleukin 1-β or in response to cellular stresses such as genotoxic, osmotic, hypoxic, or oxidative stress [38].

Apoptosis signal-regulating kinase 1 (ASK1), a MAPK3K in both the JNK and p38 signaling pathways, is activated in response to a variety of stressors, including reactive oxygen species (ROS), lipopolysaccharides (LPS), and endoplasmic reticulum (ER) stress, and Ca2+ influx, consistent with their critical roles in key cellular activities, the MAPK signaling pathways have been implicated in the pathogenesis of many human chronic diseases as cancer and neurodegenerative diseases as Alzheimer´s disease (AD), Parkinson´s disease (PD) and amyotrophic lateral sclerosis (ALS), where MAPK cascades contribute to disease progression through regulation of neuronal apoptosis, β- and γ-secretase activity, and phosphorylation of amyloid precursor protein and tau [38]. Given that the same components of MAPK signaling pathways act differentially in the pathogenic mechanism of many human diseases, have to be considered as targets in new therapeutic drugs for human diseases, as MS.

Apoptosis, Caspases and Free Radicals

The caspases, apoptosis and free radicals are also very powerful active mechanisms of chronic diseases progression [39]. During the last decades, considerable progress has been made in understanding the process of neuronal-cell death. Neuronal-cell death mediated by caspases, apoptosis and free radicals, is a common denominator in the most studied NDD as PD, AD, ALS, the post-stroke chronic phase, and MS among others. The revision of those mechanisms of disease progression is beyond the reach of this paper, but in spite that all of them are better known nowadays, had never been considered as therapeutic targets to halt NDD progression before. Their control is an important goal of the MTT here described.

The Multi-Target Therapy Designed to Control Neurodegenerative Disease´S Progression

In 2010, we postulated that in order to be able to effectively modify complex NDDs, such as MS, is essential to use polytherapy [35], adopting the successful model used in multi-resistant infections or chemotherapy schemes in cancer.

The MTT (patent MX329006 B), combines four substances that interact to produce a synergistic effect. As far as we know, this is the first treatment specifically designed to stop the progression of neurodegenerative diseases such as MS. It contains ferulic acid 50 mg, apigenin 100 mg, gamma oryzanol (GO) 50 mg and sylimarin 150 mg. It is designed to preserve the brain’s physiological micro-environment and to control the most active known pathophysiologic mechanisms involved in neurodegenerative disease progression. Because of the compound’s antioxidant properties, it has a protective effect for myelin and neurons; thus it may also be useful in other neurodegenerative oxidative-mediated diseases, such as PD [40], AD, among others. The MTT is an oral treatment designed to be taken daily and long-term to continuously combat the active pathophysiologic mechanisms involved in disease progression. It is not designed to relieve the symptoms of MS, but to slow down and control the progression of the disease. All the components have been tested previously in humans and proven to be safe for consumption [35].

Ferulic Acid

Ferulic Acid (FA) has shown protective effects against various inflammatory diseases [41]. It is an antioxidant that has proved highly effective in neutralizing free radicals such as superoxide, hydroxyl radical, and nitric oxide (NO). It acts synergistically with other antioxidants, giving them extra potency [42], and protects against nitrosamines [43]. There are no documented side effects of ingestion of FA in humans.

FA is a fenolcarboxilic acid [44] that has been shown in vitro and in vivo to decrease death of oligodendrocytes under cellular stress, which can improve neurological outcome [7]. Several mechanisms of disease can cause damage in the central nervous system that can modify the core expression of glial cells. Those effects can be produced by protein misfolding or by protein accumulation in the ER, which causes a cellular stress response and the production of neurotoxic molecules, including redox reactants like NO, reactive nitrogen-oxygen species, peroxinitrite anions and superoxide, which can cause encephalic damage [7]. FA acts against several potent cellular stress mechanisms mediated by Interleukin 1β (IL1β), cyclooxygenase-2 (COX2), inducible nitric oxide synthase (iNOS) and redox reactant synthesis, among others [45].

Syncytin is a 518-amino-acid membrane glycoprotein that may exert biological action by binding to the receptor ASCT2 (alanine, serine, cysteine transporter 2), which is both an amino acid transporter and a retrovirus receptor [46]. Viral envelope glycoproteins are known to affect immune responses and syncytin is related to activation of lymphocytes and macrophages [47]. Overexpression of syncytin in astrocytes and macrophages is sufficient to cause the cells to produce high amounts of the proinflammatory cytokine IL-1β and reactive oxygen radicals. The overexpression of syncytin is toxic to oligodendrocytes, and this toxicity is prevented by FA [48].

FA also appears to encourage the proliferation of at least some types of nerve cells, such as retinal cells [49]. It has proven to be effective in several diseases in humans and in animals. In a model of iron-induced neuronal oxidative stress and neuronal apoptosis in granular cerebellar cells [50], an increase in caspase 3 activity and apoptosis related to gene p53 activity and of its gene effector p21 was demonstrated. In neurons treated with tetrametilpirazine and FA and then exposed to the iron-induced oxidative model, a significant decrease of caspase 3 activity and expression of p53 and p21 was documented, with less severe oxidative damage and apoptosis induced by iron. This suggests that tetrametilpirazine and FA can be used to treat neurological diseases associated to oxidative stress.

Macrophage activity also has been related to neurodegenerative disease progression. FA has been shown to specifically reduce the macrophage inflammatory protein-2 (MIP-2) in the RAW264.7 macrophage cell line. Its effect was superior to that of dexamethasone [51]. FA-related compounds have potential to produce NSAID-like effects [52,53], can inhibit NO production [54] and have radical scavenging activity [52].

Apigenin

Apigenin is a flavonoid found in its natural form in several fruits and vegetables. It is well known for its anti-oncogenic, antioxidant and anxiolytic properties, acting by several mechanisms. In cases of injury or disease, microglia are recruited to the site of damage and become activated, as evidenced by morphological changes and expression of pro-inflammatory cytokines. Evidence suggests that microglia proliferate by cell division to create gliosis at the site of injury, such as the amyloid plaques in Alzheimer’s disease and the substantia nigra in PD. The hyperactivation of microglia contributes to neurotoxicity. Anti-inflammatory compounds modulate the progression of the cell cycle and induce apoptosis of activated cells, and thus might inhibit microglial proliferation [55].

Apigenin, among its structural analogues, appears to be the most potent inhibitor of the production of pro-inflammatory cytokines by lipopolysaccharide-stimulated human peripheral blood mononuclear cells [56]. Apigenin inhibits phosphorylation pathways and is a potential inhibitor of cellular autoimmunity. Due to the inhibitory activity of flavonoids on IL-4 and IL-13 synthesis, it can be expected that the intake of flavonoids, depending on the quantity and quality, may ameliorate allergic symptoms or prevent the onset of allergic diseases [57].

Apigenin is a very potent inhibitor of xanthine oxidase activity. Prostaglandin biosynthesis and NO production have been implicated in the processes of neurodegeneration, carcinogenesis and inflammation. Apigenin may be the most potent inhibitor of transcriptional activation of both COX2 and iNOS. Western and northern blot analyses demonstrated that apigenin significantly blocked protein and mRNA expression of COX2 and iNOS in LPS-activated macrophages. Transient transfection experiments showed that LPS caused an approximately 4-fold increase in both COX2 and iNOS promoter activities, but these elevations were suppressed by apigenin. This suggests that modulation of COX2 and iNOS by apigenin may be important in the prevention of carcinogenesis and inflammation [58].

The chemical chain reaction initiated by NMDA receptors and by calcium influx causes an increase in the activity of the enzyme system known as the Mitogen-Activated Protein Kinases system (MAPK). Factors released in response to hypoxia (growth factors, inflammatory cytokines and free radicals) can also stimulate the MAPK system. MAPK activity can remain elevated long after cessation of the initial stimulus. Inhibiting MAPK activity has been shown to have a neuroprotective effect in cases of central nervous system insult; and apigenin has been shown to be a strong MAPK inhibitor [59].

Decreased activity of superoxide dismutase was strongly correlated with increased oxidative damage to plasma proteins at the individual level. Intervention with apigenin seemed to partly overcome this decrease and resulted in increased levels of glutathione reductase and superoxide dismutase [60].

Sylimarine

Sylimarine is an antioxidant found in several plants and types of food. It is estimated that its antioxidant effect is 10 times stronger than that of vitamin E. It increases the hepatic content of the antioxidant enzyme glutathione by 35% and decreases free radical-mediated cellular damage by inhibition of lipoxygenase. Lipoxygenase acts in polyunsaturated fatty acids and produces leukotrienes, which are involved in cellular membrane damage [61].

Gamma Oryzanol

GO was discovered in the late 60s while experimenting with growth factors in animals. It was observed that GO accelerated animal growth with no collateral effects. It is a compound molecule made up of FA and estherol.

When GO is taken orally, absorption is low  Once absorbed by the digestive system, it is hydrolyzed by a non-specific esterase, separating it into free FA and estherol. When administered alone, FA absorption increases by a factor of 20 to 30 because it is a hydrosoluble compound, thus eliminating the issue of cellular transport. Also, free FA does not undergo first pass metabolism by the liver as GO does. Nevertheless, GO is an additional source of FA that increases the level of this antioxidant, providing additional effect [62].

Materials and Methods

Clinical Stabilization Treatment Trial

The different substances of the MTT, synergistically working against the most important known pathophysiologic mechanisms of disease progression and involved in primary and secondary MS forms, including pathophysiologic oxidation, mitochondrial degeneration, cellular damage mediated by macrophage free radicals, caspase activation, aberrant apoptosis, syncytin mediated immune activation, and MAPK cellular damage, could preserve the physical and functional integrity of the myelin-axon unit, the neurovascular unit, and the neurons and glial cells, achieving clinical stability in neurodegenerative disease. It is the first, and as far as we know, the only therapy that combats the most known mechanisms of disease progression simultaneously. As the MTT has no effect on the clinical symptoms of MS, it does not replace standard symptomatic treatment.

With our hospital ethics committee approval, a group of 33 subsequent patients were included with MS according to Mc Donald´s criteria that accepted to participate as volunteers and signed an informed consent form. There was no randomization and/or blinding. The primary endpoint was the Expanded Disability Status Scale (EDSS) score during the follow up period (a lower score indicates better clinical condition). Before beginning the trial, we optimized the symptoms of each participant and recorded their basal EDSS score. Then, we added the MTT as a monotherapy, without using any other treatment to control MS progression, at a dose of 1 pill PO every 12 hours taken on an empty stomach. We evaluated all patients with clinical examination, EDSS scoring and laboratory testing every 3 months during the follow-up period of up to 94 months

Results

A group of 33 patients with MS were studied, age 19 to 60 years (mean 37.12 years, SD +/-12.05), 19 female (57.6%), 14 male (42.4%). The basal EDSS score was 0-8 (mean 2.43, SD +/- 2.47). Maximum follow-up period was 94 months, mean 40.7 months. There were 13 patients (39.39 %) that improved their basal EDSS score and 17 patients (51.51%) had no increase in their EDSS score during the follow up period. Overall, 30 patients (90.9%) remained with the same or better EDSS score during the follow up. The mean EDSS at 64 months of follow up was 2.7 (n=11). The EDSS was worse in 3 patients (9 %), documented only in patients with progressive forms. In the subgroup where progressive variants were excluded (n=26), there were 12 patients (46.2%) that improved their basal EDSS score and 14 patients (53.8%) had no increase in their EDSS score. None of the patients in this subgroup had a worse EDSS score in the follow up period. The mean basal EDSS was 0 to 8 (mean 1.9), and at 64 month of follow up was 0.8 (n=7). At 76 months of follow up, the mean EDSS score was 0.25 (n=4). No adverse effects were observed while using the MTT.

Figure 1. Disease progression control in MS patients using the MTT as a monotherapy treatment. The score of historic MS patients would increase as time went on, affecting their quality of life (orange line) [63]. In MS patients treated with the MTT, the disease has a very slow clinical progression or improvement in most of the cases during the follow up period (blue line).

Figure 2. Disease progression control in the subgroup where progressive variants were excluded (n=26), using the MTT as a monotherapy treatment. There was no deterioration in EDSS score in any patient during the follow-up, up to 94 months (blue line) vs expected deterioration of the natural course of the disease (orange line) [63].

Discussion

One of the most important challenges in MS is controlling disease progression. The MS progression index has been established in a deterioration of 0.67 points in the EDSS per year. By extrapolation, MS patients would have an EDSS of 1.34 points at 24 months, 2.68 points at 48 months, and 4.69 at 84 months. This disease progression index means that MS leads to a wheelchair dependency on average after 10 years [63]. It is necessary to have new therapeutic resources to stop the disease progression and improve patient outcomes.

At present, all drugs approved for the treatment of MS had been designed or adopted to modify the immunological function, but none of them prevents or mitigates the most important known mechanisms involved in MS progression here described or avoid the targeting of the myelin by the immune system. The potential drugs being tested for the treatment of MS also have this conceptual deficiency and lack of pharmaceutical mechanism of action directed towards these important therapeutic targets.

The MTT differs radically from all the other MS treatment, as it is the first treatment designed and tested based in those mechanism of actions. In the group of MS patients treated with the MTT as monotherapy, we found a consistent disease progression control in most of the patients during the follow-up (up to 94 months, mean 40.7 months). It was an improvement in the clinical condition according to the EDSS in the population that reached the 60 months of follow-up. The explanation of this improvement could be, that if we control the wider number of mechanism of disease progression, neuroplasticity and reorganization of function mechanism are more effective, than if those mechanism remains active [64-67], and may not be a spontaneous event.

Conclusions

The MTT is the first therapy specifically designed to halt the progression of NDD in general and MS in particular, that combats the most known mechanisms of disease progression simultaneously, including syncytin-mediated neuroinflammation. With this initial evidence, we believe that the MTT may be able to change the course of MS and control its progression. A double blinded, multicenter study is required to evaluate its efficacy in other populations and geographical conditions. The MTT represents a new pharmacological strategy in MS treatment, that may be useful to control the disease progression.

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