Effect of Preventive and Curative Fingolimod Treatment Regimens on Microglia Activation and Disease Progression in a Rat Model of Multiple Sclerosis

Reduction in experimental autoimmune thyroiditis by IgG Fc fragments bearing regRF epitopes

Previously, we identified a new immunoregulatory factor, the production of which provides rats with resistance to certain experimental autoimmune diseases. It has been named regulatory rheumatoid factor (regRF). RegRF inhibits the expansion of CD4 T lymphocytes by killing activated cells. CD4 T cells are essential for antibody production against a majority of antigens and for the generation of cytotoxic T cells; therefore, regRF is an attractive therapeutic biotarget for T-cell and antibody-mediated autoimmune diseases. RegRF is anti-idiotypic antibodies that have a shared paratope in addition to an individual paratope. Epitopes specific to the shared regRF paratope (regRF epitopes) can be obtained on conformers of IgG Fc fragments. Immunization with Fc fragments carrying regRF epitopes reduces rat collagen-induced arthritis and diminishes experimental autoimmune encephalomyelitis. The aim of this study was to determine whether IgG Fc fragments bearing regRF epitopes suppress experimental autoimmune thyroiditis (EAT). Four weeks after EAT induction, rats were immunized with IgG Fc fragments exhibiting regRF epitopes. Histology studies of the thyroid were performed 4 weeks later. Thyroid function and other parameters were also evaluated. Treatment of rats with Fc fragments bearing regRF epitopes decreased the number of rats affected by EAT, significantly decreased the extent of thyroid damage, prevented thyroid metaplasia, and restored normal thyroid hormone production. Therefore, RegRF is a promising biotarget in autoimmune thyroiditis, and Fc fragments bearing regRF epitopes are a potential therapeutic agent for that condition.

Role of Brain Imaging in Drug Development for Psychiatry

Background:

Over the last decades, many brain imaging studies have contributed to new insights in the pathogenesis of psychiatric disease. However, in spite of these developments, progress in the development of novel therapeutic drugs for prevalent psychiatric health conditions has been limited.

Objective:

In this review, we discuss translational, diagnostic and methodological issues that have hampered drug development in CNS disorders with a particular focus on psychiatry. The role of preclinical models is critically reviewed and opportunities for brain imaging in early stages of drug development using PET and fMRI are discussed. The role of PET and fMRI in drug development is reviewed emphasizing the need to engage in collaborations between industry, academia and phase I units.

Conclusion:

Brain imaging technology has revolutionized the study of psychiatric illnesses, and during the last decade, neuroimaging has provided valuable insights at different levels of analysis and brain organization, such as effective connectivity (anatomical), functional connectivity patterns and neurochemical information that may support both preclinical and clinical drug development. Since there is no unifying pathophysiological theory of individual psychiatric syndromes and since many symptoms cut across diagnostic boundaries, a new theoretical framework has been proposed that may help in defining new targets for treatment and thus enhance drug development in CNS diseases. In addition, it is argued that new proposals for data-mining and mathematical modelling as well as freely available databanks for neural network and neurochemical models of rodents combined with revised psychiatric classification will lead to new validated targets for drug development.

Phytoconstituents from ten natural herbs as potent inhibitors of main protease enzyme of SARS-COV-2: In silico study

BACKGROUND

Lack of treatment of novel Coronavirus disease led to the search of specific antivirals that are capable to inhibit the replication of the virus. The plant kingdom has demonstrated to be an important source of new molecules with antiviral potential.

PURPOSE

The present study aims to utilize various computational tools to identify the most eligible drug candidate that have capabilities to halt the replication of SARS-COV-2 virus by inhibiting Main protease (Mpro) enzyme.

METHODS

We have selected plants whose extracts have inhibitory potential against previously discovered coronaviruses. Their phytoconstituents were surveyed and a library of 100 molecules was prepared. Then, computational tools such as molecular docking, ADMET and molecular dynamic simulations were utilized to screen the compounds and evaluate them against Mpro enzyme.

RESULTS

All the phytoconstituents showed good binding affinities towards Mpro enzyme. Among them laurolitsine possesses the highest binding affinity i.e. -294.1533 kcal/mol. On ADMET analysis of best three ligands were simulated for 1.2 ns, then the stable ligand among them was further simulated for 20 ns. Results revealed that no conformational changes were observed in the laurolitsine w.r.t. protein residues and low RMSD value suggested that the Laurolitsine-protein complex was stable for 20 ns.

CONCLUSION

Laurolitsine, an active constituent of roots of Lindera aggregata, was found to be having good ADMET profile and have capabilities to halt the activity of the enzyme. Therefore, this makes laurolitsine a good drug candidate for the treatment of COVID-19.

Guggulsterone ameliorates ethidium bromide-induced experimental model of multiple sclerosis via restoration of behavioral, molecular, neurochemical and morphological alterations in rat brain

Multiple Sclerosis (MS) is a progressive neurodegenerative disease with clinical signs of neuroinflammation and the central nervous system's demyelination. Numerous studies have identified the role of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) overexpression and the low level of peroxisome proliferator-activated receptor-gamma (PPAR-γ) in MS pathogenesis. Guggulsterone (GST), an active component derived from 'Commiphora Mukul,' has been used to treat various diseases. Traditional uses indicate that GST is a suitable agent for anti-inflammatory action. Therefore, we assessed the therapeutic potential of GST (30 and 60 mg/kg) in ethidium bromide (EB) induced demyelination in experimental rats and investigated the molecular mechanism by modulating the JAK/STAT and PPAR-γ receptor signaling. Wistar rats were randomly divided into six groups (n = 6). EB (0.1%/10 μl) was injected selectively in the intracerebropeduncle (ICP) region for seven days to cause MS-like manifestations. The present study reveals that long-term administration of GST for 28 days has a neuroprotective effect by improving behavioral deficits (spatial cognition memory, grip, and motor coordination) associated with lower STAT-3 levels. While elevating PPAR-γ and myelin basic protein levels in rat brains are consistent with the functioning of both signaling pathways. Also, GST modulates the neurotransmitter level by increasing Ach, dopamine, serotonin and by reducing glutamate. Moreover, GST ameliorates inflammatory cytokines (TNF, IL-1β), and oxidative stress markers (AchE, SOD, catalase, MDA, GSH, nitrite). In addition, GST prevented apoptosis, as demonstrated by the reduction of caspase-3 and Bax. Simultaneously, Bcl-2 elevation and the restoration of gross morphology alterations are also recovered by long-term GST treatment. Therefore, it can be concluded that GST may be a potential alternative drug candidate for MS-related motor neuron dysfunctions.