Journal of Multiple Sclerosis

A Novel Synthetic Peptide is Reviewed

Adam Hoffman^{* *}Correspondence: Adam Hoffman, Department of Medicine, University of Florida, United States, Email:

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Introduction

The response of Central Nervous System (CNS) cells to infections as well as to immune system cells invading the brain and spinal cord are referred to as neuroinflammation [1]. By raising levels of pro-inflammatory cytokines, proteases, glutamate, free radicals, and excessive glial cell activation in the CNS, an extended or extremely strong inflammatory response induces neuronal death. As seen in a variety of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, ischemic injury, and multiple sclerosis, the origin of neuroinflammation can be multifactorial and include infections, accumulation of toxic metabolites in obese or aging individuals, chemotherapy-related cognitive impairment, and peptides or proteins. Lipopolysaccharide (LPS), a lipopolysaccharide found in the membrane of Gram-negative bacteria, is a trigger of the inflammatory process that can exacerbate the response and induce the production of reactive molecules that directly damage cells by activating cascades of reactions that may cause sepsis and death. It is also related to neuroinflammation which can cause the onset of neurodegenerative diseases. From a therapeutic perspective, forms of treatment that address both bacteria and LPS are extremely desirable [2]. Antimicrobial Peptides (AMPs), which serve as mediators in situations of common infections, hospital sepsis, or bacterial resistance by slowing the growth or damaging the membranes of invading cells, have become the focus of research in the hunt for a novel form of therapy. Due to their shared ecological niches with bacteria, fungi and bacteria end up competing with one another. As a result, they have developed chemicals like AMP that can destroy their rivals. An alternative in the search for the control and/or combat of harmful organisms is the use of novel compounds from organisms like fungi. Candida albicans, a pathogenic fungus that thrives in the mouth, gastrointestinal tract, and external reproductive system of the majority of people on Earth, can compete with human pathogenic bacteria and can produce candidalysin, a cationic cytolytic peptide toxin. Candidalysin has already produced immunomodulatory effects at lower concentrations (1.5–15 M), such as DNA binding of c-Fos, G–CSF, and GM– CSF. Additionally, concentrations of 70 M can already cause cell damage and the release of cytokines linked to damage, such as IL-1 and IL-6 [3]. Because fungi can kill or suppress other microorganisms when they transform into their filamentous form and cause candidiasis, the cytolytic peptide toxin candidalysin is essential for the pathogenesis of C. albicans fungi [3]. As such, it may be exploited in drug design to modify its action. As a new alternative chemical with promise against neurological illnesses, bacterial infections, and cancer, the current work suggests evaluating the antineuroinflammatory activity of synthetic peptides based on the protein sequence coming from the candidalysin of the fungus C. Albicans.

Discussion

According to studies, the physicochemical characteristics of peptides are linked, meaning that changes in one or more of the parameters might significantly affect the others. Designing novel peptides with enhanced potency and selectivity may depend on comprehending and managing these interrelationships. The rational peptide design suggested takes into account the shortening of the candidalysin, which is associated with identical parameters of maintenance antibacterial action and reduces toxicity. The major frequency of charge for the deposited AMPs on APD is +3, and the hydrophobicity ranges from 45 to 55%, according to an analysis of the physical-chemical parameters. To maintain the charge at the maximum frequency recorded in the database, Gln and Lys were exchanged [4]. To promote helix-helix packing and improve electrostatic and van der Waals interaction, Gly was substituted for Iso. Lys can be replaced with Leu to improve the hydrophobic moment and stabilize the helical shape. When compared to candidalysin, the amino acid alterations brought on by the definition of amphipathicity result in a greater rearrangement of the hydrophobic moment. The effectiveness of cell binding and penetration appears to rise with an increase in the hydrophobic moment. Due to the lack or minimal presence of negative side effects, the low proportion of hemolysis in antibacterial, anticancer, and antiinflammatory peptides is a significant feature in the synthesis of new bioactive compounds. Low concentrations (1 to 20 M) of the Ca-MAP1 peptide have no hemolytic effect. In contrast, the cytolytic toxin candidalysin has been shown to completely hemolyze erythrocytes at a concentration of 10 M in the literature. At concentrations of 18.1 M, the Ca-MAP1 peptide reduced the growth of K. pneumoniae ATCC bacteria and had bactericidal effects. At a dose of 9.1 M, the E. coli KPC bacteria's growth was impeded, but at 36.3 M, all bacterial cells were destroyed. At a concentration of 32 g.mL-1 (96.5 mM), ciprofloxacin reduced growth but did not exhibit bactericidal activity. In contrast to the Ca-MAP1 peptide, the antibiotic ciprofloxacin takes longer to start acting as an antibacterial than does this bacterial membrane permeabilization generated by the E. coli bacterium [5]. At the lowest MIC of 9.1 M, like in the case of E. coli, the CaMAP1 peptide was effective in preventing Gram-negative bacterial growth, and at the same dose, there was only moderate hemolysis in blood cells. However, sepsis and inflammation are brought on by the release of Lipopolysaccharide (LPS) from the lysis of Gram-negative bacteria at picomolar quantities [6]. Immune and inflammatory responses in the central nervous system and neurodegenerative disorders are significantly influenced by activated microglial cells. During neuroinflammation, signaling molecules are generated that mediate numerous pro-apoptotic pathways. A transcription factor called NF-B, which is linked to the pathogenesis of many neurodegenerative illnesses, begins and controls the development of many inflammatory processes in glial cells during inflammation. It is already known that Toll-like Receptor (TLR) signaling causes LPS, an endotoxin found in the outer membrane of Gram-negative bacteria, to cause systemic inflammatory response syndrome. PI3K/AKT, MAPK, and mTOR are a few of the signal transduction pathways that are activated when LPS binds to TLR4 on the surface of microglia; these pathways ultimately cause the activation of NF-B. The production of pro-inflammatory cytokines, chemokines, Inducible Nitric Oxide Synthase (iNOS), and COX-2 is then mediated by NF-B activation, which results in neuroinflammation. It is possible to think of NO generation inhibition in LPS-induced BV-2 cells as a successful therapy for CNS inflammation [7]. In LPS-stimulated BV-2 cells, the Ca-MAP1 peptide's NO inhibitory activities were assessed, and the cytotoxic effects of these peptides were determined using the MTT assay. Ca-MAP1 suppressed the byproduct NO while exhibiting no cytotoxicity (nitrite). One of the most popular and efficient traditional therapies for cancer patients is chemotherapy. Additionally, it has been shown that cognitive issues may arise in 70% of cancer patients receiving chemotherapy during or after treatment, which lowers their quality of life. Chemotherapy is known to have negative effects on brain function, leading to dysfunctions in executive function, learning, memory, attention, and motor activity. Additionally, several investigations have demonstrated that alkylating compounds, microtubule inhibitors, antimetabolites, and tyrosine kinases can cause neurotoxicity. Doxorubicin is a member of the anthracycline class and is frequently used as part of chemotherapy for lung, breast, and hematologic cancers. Doxorubicin inhibits topoisomerase II and inserts DNA to produce its anticancer effects [8]. Using doxorubicin as an antineoplastic standard, Ca-anticancer MAP1's activity was assessed in this context against the tumor cell lines RD, HeLa, and NCI-H292 as well as the normal cell lines MRC-5 and BV-2. When compared to Ca-MAP1 results, the NCI-H292 strain of human lung cancer, which belongs to the NCI family and is of the H292 type, demonstrated the highest level of doxorubicin resistance. Doxorubicin displayed a greater IC50 than Ca-MAP1 when the IC50 values of the two drugs were compared in NCI-H292 cells. Additionally, Ca-MAP1 displayed a 1.35-times lower IC50 than DOX, indicating a higher level of cytotoxicity toward NCI-H292. Additionally, the derivative had reduced cytotoxicity for erythrocytes, human fibroblast lineage MRC-5, and neuronal microglia lineage BV-2 in 18.1 M compared to doxorubicin. The Ca-MAP1 peptide did not exhibit an influence on cellular viability close to 50%, hence the software did not calculate the IC50 for MRC-5. The Ca-MAP1 concentration used for the NO assay in the case of the BV-2 cell line was not cytotoxic. As a result, it exhibits greater activity than the positive control without adversely affecting erythrocytes, BV-2 cell line, or MRC5 cell line in vitro. Following the activity assay, conformational analysis in silico and in vitro was the following stage. The Ramachandran plot can be used to evaluate the in silico studies on the development of a structural homology-based model that suggested the potential production of a -helix. The validation scores for the predicted three-dimensional structure show that the structural homology-based prediction was accurate. In the righthanded -helix quadrant, Ca-MAP1 displayed 92.86% of the amino acid residues in the preferred areas, 7.14% in the authorized region, and none in the prohibited region. Additionally, the peptide Ca-MAP1 displays a suitable backbone geometry Rama-Z of 1.85 to 1.76. Circular dichroism analysis of proteins allowed for the observation of the distinctive peptide bond spectra around 190 nm, and in particular, in the bands around 208 and 222 nm, it was feasible to infer the construction of a helical structure, which was supported by in silico studies. Ca-MAP1 indicated the presence of two negative bands at roughly 208 and 222 nm and two positive bands in the circular dichroism. In the presence of TFE and SDS, it is plausible to suppose that the peptide displays a secondary-helical or 310-helical structure that has close bands in the above values. The circular dichroism of the cytolytic peptide candidalysin in the HEPES buffer exhibits the creation of a helical helix. The peptide Ca-MAP1 can form a random coil, as evidenced by the wide negative band around 199 nm and the absence of any other negative bands in the analysis of circular dichroism in the presence of water. This conclusion is supported by the molecular dynamics of the peptide RMSD, RMSF, SASA, and Rg fluctuations in the presence of water [9]. To see if there is a correlation between in silico and in vitro studies, more environments, such as SDS 30 mM and TFE 50%, need to be explored in silico with molecular dynamics. Circular dichroism has been used in several studies [10] to show conformational changes for antimicrobial peptides in hydrophobic or hydrophilic environments. The CD analyses reveal that Ca-MAP1 preferred the -helix conformation in a hydrophobic environment, indicating that the protein's structure supports the membrane permeabilization mechanism that was shown in the Sytox Green assay. This finding is consistent with work by Migliolo et al., who showed that an alanine-rich peptide causes membrane rupture and helicoidal shape. Similar activity and structural behavior have been seen in other peptides in the literature; cationic-helix amphipathic peptides, in particular, have been welldocumented for their antimicrobial action, particularly antibacterial activity. Animal venom peptide is more frequently exploited for the development of new medications than mycotoxin peptide derivatives, which have not received as much research. Other peptide toxin derivatives have shown comparable characterization results. The venom peptides TsAP-1 and TsAP2 from the Brazilian yellow scorpion (Tityus serrulatus) have diverse functions, with the first having a low hemolytic and bactericide activity at 120 to 160 M. At 5 to 10 M, the second is more potently bactericidal and hemolytic. The addition of lysin to TsAP peptides increases net charge, which increases hemolytic activity but also greatly boosts the antibacterial and anticancer properties, dropping the IC50 from 320 M to 5 M. The venom peptide Hp1404 from the scorpion Heterometrus petersii has been successfully converted into new peptide derivates by exchanging amino acids to leucine and lysine. The derivates showed less hemolytic effect and antibacterial effect on multidrug-resistant Pseudomonas aeruginosa in the concentration range of 0.78 to 25 M, and all derivates had an amphipathic cationic. The synthetic cationic peptides Hp-MAP1 and Hp-MAP2, which are derived from the peptide toxin temporin-PTA of the amphibian Hylarana picturata, exhibit antibacterial activity at concentrations between 2.8 and 92 M without hemolyzing erythrocytes. In molecular dynamics, these peptides exhibit a -helix in the presence of hydrophobic and anionic environments and can interact with s To detect the interactions between the membrane phospholipids and the CaMAP1 peptide, molecular dynamics in the presence of membranes mimicked by 1,2-dipalmitoylsn-glycerol-3- phosphatidylglycerol (DPPG-anionic) and 1,2-dipalmitoyl-sn-lyco-3 phosphatidylethanolamine (DPPE-neutral) are required. Other substances found in animal venom are equally significant from a biotechnological standpoint. For example, the Brazilian snake Bothrops moojeni produces phospholipase A2, which is crucial for its anticancer properties and can be collected in lung mucoepidermoid carcinoma NCI-H292 cell lines at a concentration of 9.2 M. Another example is the Vespa velutina species of wasp and bee venom, which has antibacterial activity against Gramnegative and positive bacteria as well as an anti-inflammatory effect against LPS-induced BV-2 inflammations [10].

Conclusion

In conclusion, Ca-MAP1 was developed using a rational design method and was bioinspired by a fungal toxin. This article presents an initial evaluation of Ca-potential MAP1's antibacterial, anti-neuroinflammatory, and anticancer properties for the first time. It may be possible to employ the peptide Ca-MAP1 to reduce the severity of immunological reactions brought on by bacterial infections that generate toxins and waste products. Notably, NCI-H292 had more selective efficacy than the antineoplastic medication doxorubicin against a rare metastatic human lung cancer. More research is required to better characterise it and understand the underlying mechanisms of action.

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