David Magalashvili

Microarray analysis identifies altered regulation of nuclear receptor family members in the pre-disease state of multiple sclerosis

Molecular mechanisms that influence susceptibility to multiple sclerosis are poorly understood. We analyzed peripheral blood gene expression profiles in nine healthy subjects up to nine years before the onset of multiple sclerosis in comparison with 11 age-, gender-, and origin-matched healthy subjects who remained multiple sclerosis-free, and 31 subjects during the first clinical episode of multiple sclerosis. Within the 1051 highly variable genes that differentiated between multiple sclerosis-to-be and multiple sclerosis-free subjects, we identified activation of TCR signaling that triggered the Cbl and MAPK cascade in concert with downstream synergic over-expression of NFAT and MEF2B, but failed to augment the expression of the nuclear receptor gene family members NR4A1, NR2F1, VDR and MEF2B, that further resulted in impaired apoptotic machinery. Comparison between multiple sclerosis-to-be and first clinical onset of multiple sclerosis operating module networks demonstrated the evolution of altered regulation of nuclear receptor-dependent apoptosis. Our findings demonstrating a silent multiple sclerosis trait that is associated with suppressed expression of the nuclear receptor network and inhibited apoptosis of activated T-cells support the role of these transcription signals in the evolution of the autoimmune processes that operate in the pre-disease stage of multiple sclerosis.

Modeling of cognitive impairment by disease duration in multiple sclerosis: a cross-sectional study.

Background/Aims Large-scale population studies measuring rates and dynamics of cognitive decline in multiple sclerosis (MS) are lacking. In the current cross-sectional study we evaluated the patterns of cognitive impairment in MS patients with disease duration of up to 30 years. Methods 1,500 patients with MS were assessed by a computerized cognitive battery measuring verbal and non-verbal memory, executive function, visual spatial perception, verbal function, attention, information processing speed and motor skills. Cognitive impairment was defined as below one standard deviation (SD) and severe cognitive impairment as below 2SD for age and education matched healthy population norms. Results Cognitive performance in our cohort was poorer than healthy population norms. The most frequently impaired domains were information processing speed and executive function. MS patients with secondary-progressive disease course performed poorly compared with clinically isolated syndrome, relapsing-remitting and primary progressive MS patients. By the fifth year from disease onset, 20.9% of patients performed below the 1SD cutoff for impairment, p = 0.005, and 6.0% performed below the 2SD cutoff for severe cognitive impairment, p = 0.002. By 10 years from onset 29.3% and 9.0% of patients performed below the 1SD and 2SD cutoffs, respectively, p = 0.0001. Regression modeling suggested that cognitive impairment may precede MS onset by 1.2 years. Conclusions The rates of cognitive impairment in this large sample of MS patients were lower than previously reported and severe cognitive impairment was evident only in a relatively small group of patients. Cognitive impairment differed significantly from expected normal distribution only at five years from onset, suggesting the existence of a therapeutic window during which patients may benefit from interventions to maintain cognitive health.

Effect of Alfacalcidol on multiple sclerosis-related fatigue: A randomized, double-blind placebo-controlled study

Context: Fatigue is one of the most common and disabling symptoms of multiple sclerosis (MS); however, there is no medication that has been approved specifically to treat MS-related fatigue. Objective: We aimed to evaluate the effect of vitamin D analogue, Alfacalcidol, on MS-related fatigue. Design, settings, participants: This was a randomized, double-blind, parallel group, placebo-controlled trial in patients with clinically definite MS by McDonald criteria conducted in a single university-affiliated medical center in Israel. Randomly selected patients from the Sheba MS Registry computerized database (N=600) were assessed using the self-report Fatigue Severity Scale (FSS). Patients with clinically meaningful fatigue (N=259) were further assessed for trial eligibility, and MS patients with significant fatigue (N=158; 61%, 118 females, mean age 41.1 ± 9.2 years and mean disease duration of 6.2 ± 5.5 years) were included in the study and randomized to receive treatment or placebo. Intervention: Alfacalcidol (1 mcg/d, N=80) or placebo (N=78) was administered for six consecutive months. Main outcome measure: The primary endpoint of the study was the change between Alfacalcidol and placebo-treated patients in the Fatigue Impact Scale (FIS) score; the cut-off point for improvement was defined as 30% decrease. All analyses followed the intention-to-treat principle and were performed for all participants based on the group they were randomly allocated regardless of whether or not they dropped out. Results: Alfacalcidol decreased the mean relative FIS score as compared with placebo (–41.6% vs. –27.4%, p=0.007, respectively). This advantage was further emphasized when the modified FIS (MFIS) relative change was calculated. Quality of Life (QoL) improved in Alfacalcidol-treated patients as compared with placebo in the RAYS psychological (p=0.033) and social (p=0.043) sub-scales. The Alfacalcidol-treated group had reduced number of relapses (p=0.006) and higher proportion of relapse-free patients (p=0.007). Reduction of relapses by Alfacalcidol became significant at 4 months of treatment, was sustained at 6 months and decayed 2 months after drug discontinuation. Alfacalcidol treatment was safe and no serious adverse events were recorded. Conclusion: Alfacalcidol is a safe and effective treatment strategy to decrease fatigue and improve QoL in patients with MS.

Long term safety of IVIg therapy in multiple sclerosis: 10 years experience

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system. The majority of MS patients have a relapsing–remitting course with progressive neurological disability that accumulates over the years. Intravenous Immunoglobulin (IVIg) has demonstrated benefit in the treatment of some patients with relapsing–remitting MS. Concerns about adverse events of IVIg, mainly acute renal failure and thromboembolic events have been raised in the medical literature. We examined the adverse events profile of IVIg treatment in a large cohort of 293 relapsing–remitting MS patients treated with an initial loading dose of IVIg (0.4 g/Kg body weight/day, for 5 consecutive days) and additional booster dose infusions (0.4 g/Kg body weight/booster dose, every 6 weeks) as a maintenance treatment. A total of 9281 IVIg infusions were administered within a mean treatment period of 3.8 ± 3.5 years (3 months–10 years). The main adverse event during the loading dose period was headache, occurring in 12.6% of the patients. The annual rate of any adverse event during the IVIg maintenance period was 4.4% during the first year and had a trend to decrease with every passing year of treatment. Adverse events during the loading dose did not predict adverse events during the maintenance phase. No severe adverse events were recorded. We conclude that IVIg is a safe therapy in MS either for short or for long-term periods.

Suppressed RNA-polymerase 1 pathway is associated with benign multiple sclerosis.

Benign multiple sclerosis (BMS) occurs in about 15% of patients with relapsing-remitting multiple sclerosis (RRMS) that over time do not develop significant neurological disability. The molecular events associated with BMS are not clearly understood. This study sought to underlie the biological mechanisms associated with BMS. Blood samples obtained from a cohort of 31 patients with BMS and 36 patients with RRMS were applied for gene expression microarray analysis using HG-U133A-2 array (Affymetrix). Data were analyzed by Partek and pathway reconstruction was performed by Ingenuity for the most informative genes (MIGs). We identified a differing gene expression signature of 406 MIGs between BMS patients, mean±SE age 44.5±1.5 years, 24 females, 7 males, EDSS 1.9±0.2, disease duration 17.0±1.3 years, and RRMS patients, age 40.3±1.8 years, 24 females, 12 males, EDSS 3.5±0.2, disease duration 10.9±1.4 years. The signature was enriched by genes related RNA polymerase I (POL-1) transcription, general inflammatory response and activation of cell death. The most significant under-expressed pathway operating in BMS was the POL-1 pathway (p = 4.0*10−5) known while suppressed to activate P53 dependent apoptosis and to suppress NFκB induced inflammation. In accordance, of the 30 P53 target genes presented within the BMS signature, 19 had expression direction consistent with P53 activation. The transcripts within the pathway include POL-1 transcription factor 3 (RRN3, p = 4.8*10−5), POL-1 polypeptide D (POLR1D, p = 2.2*10−4), leucine-rich PPR-motif containing protein (LRPPRC p = 2.3*10−5), followed by suppression of the downstream family of ribosomal genes like RPL3, 6,13,22 and RPS6. In accordance POL-1 transcript and release factor PTRF that terminates POL-1 transcription, was over-expressed (p = 4.4*10−3). Verification of POL-1 pathway key genes was confirmed by qRT-PCR, and RRN3 silencing resulted in significant increase in the apoptosis level of PBMC sub-populations in RRMS patients. Our findings demonstrate that suppression of POL-1 pathway induce the low disease activity of BMS.

Polymerase-1 pathway activation in acute multiple sclerosis relapse

BACKGROUND Increased expression of RNA polymerase 1 (POL1) molecular pathway was reported to be associated with increased disease activity in patients with multiple sclerosis (MS). However, the operating molecular mechanisms that characterize the pattern of acute MS relapse activity has not been thoroughly studied. OBJECTIVE To assess POL1 pathway expression during acute MS relapse. METHODS We studied POL1 pathway associated biomarkers during the first acute optic neuritis attack of MS, and in relapsing-remitting MS patients treated with disease-modifying drugs (DMDs) experiencing an acute MS relapse or a radiological relapse using gene expression microarrays and quantitative RT-PCR. RESULTS In MS patients (N = 6) during the first acute optic neuritis attack POL1 pathway activation was evident by over-expression of POL1 related network including transcription factor UBTF and downstream components of Assembly of RNA POL1 complex (p=1.92E-03). POL1 related biomarkers RRN3, POLR1D and LRPPRC were over-expressed x1.6 (p = .002), ×1.7 (p = .01) and x2.0 (p = .001) times higher respectively, in MS patients (N = 30) during acute clinical relapse as compared with remission. Similarly, in MS patients (N = 21) that presented with a radiological relapse, we observed significant activation of POL1 related biomarkers including RRN3 (p = .01), POLR1D (p = .002), POLR1E (p = .0001) and LRPPRC (p = .006), as compared with remission, as well as overexpression of a large group of genes encoding ribosomal proteins like RPS6KA3 (p = 7.2E-6), RRP8 (p = .0002) and RPCS9 (p = .0008). CONCLUSIONS Our findings demonstrated increased POL1 pathway activity in acute MS relapse and suggest that targeted inactivation of POL1 pathway represent a novel strategy for a better treatment of acute MS relapse.