Current Medicinal Chemistry - Volume 25, Issue 19, 2018

Background: Spontaneous intracerebral haemorrhage (ICH) is a relatively common fatal disease, with an overall global incidence estimated at 24.6 per 100,000 person- years. Given the high degree of morbidity and mortality associated with ICH, therapies that may have neuroprotective effects are of increasing interest to clinicians. In this last context, cell therapies offer the promise of improving the disease course which cannot be addressed adequately by existing treatments. Objective: The aim of this review is to evaluate the protective effects and molecular mechanisms of mesenchymal stem cells (MSCs) on haemorrhagic brain following ICH. We also discuss possible emerging therapeutic approaches worth of further research. Methods and Results: The available literature on the therapeutic potential of MSCs in ICH animal models clearly demonstrated that MSCs enhance the functional recovery and reduce the volume of the infarct size exerting anti-inflammatory and angiogenic properties. However, the quality of the original articles investigating the efficacy of stem cell therapies in ICH animal models is still poor and the lack of ICH clinical trial does not permit to reach any relevant conclusions. Conclusion: Further studies have to be implemented in order to achieve standardized methods of MSCs isolation, characterization and administration to improve ICH treatments with MSCs or MSC-derived products.

Genetic background accounts for only 5 to 10% of the reported cases of Parkinson's disease (PD), while the remaining cases are of unknown etiology. It is believed that environmental factors may be involved in the causality of a large proportion of PD cases. Several PD genes are activated by xenobiotic exposure, and a link between pesticide exposure and PD has been demonstrated. Many epidemiological studies have shown an association between PD and exposure to metals such as mercury, lead, manganese, copper, iron, aluminum, bismuth, thallium, and zinc. This review explores the biological effects, the pathogenetic processes, genetic susceptibilities to metals as well as examining future strategies for PD treatment, such as chelation therapy.

Background: Nowadays, allergen-specific immunotherapy (AIT) is the only treatment able to modulate the course of allergic diseases. Although it has been applied for the last 100 years, treatment with whole allergen extracts is not without its drawbacks: AIT can cause local and systemic adverse events and may produce new IgE sensitization against other allergens present in the extract. Furthermore, the lengthy treatment duration (3-5 years), frequent administration, and high cost of treatment are other disadvantages. For these reasons, there is a need for safer and more effective AIT strategies. One promising approach is the use of synthetic peptides representing the B- or T-cell epitopes of allergens. Objective: This review summarizes the main advances in peptide immunotherapy, from preclinical models to early clinical trials, focusing on house dust mite, bee venom, cat allergy, and Oleaceae pollinosis. Results: Following an extensive review of the relevant literature, we summarize how peptide therapies may change the course of allergic diseases and promote allergen tolerance, thereby ameliorating the main disadvantages of AIT. Although the molecular mechanisms involved are not yet fully defined, they seem to depend on structure, length, peptide sequence, and route of administration. This novel immunotherapy has been demonstrated to modulate the immune system, promoting regulatory T-cell induction and Th2 inhibition. This tolerance-inducing potential has led this therapy to be termed SPIRE (synthetic peptide immuno-regulatory epitopes). Conclusion: Experimental models and clinical trials have demonstrated the usefulness of SPIRE treatment to cure these diseases, opening a new era in allergen therapeutics.

Background: Antibiotic resistance is one of the biggest threats to global health today, leading to higher medical costs and increased mortality. Because of the emergence and rapid spread of new resistance mechanisms globally, a growing number of infections are becoming harder to treat as the antibiotics used to treat them become less effective. Therefore, the development of new effective antimicrobial agents is still urgently needed. In last decades, a large number of structurally novel spirooxindoles have been synthesized mainly based on the ylide intermediates generated in situ and further assessed for their antimicrobial activity against different types of bacteria, leading to the discovery of some potent lead compounds with antimicrobial potentials. Objective: The aim of this review to submarize recent advances on the synthesis, structure- activity relationship studies (SARs) and antimicrobial activity of spirooxindoles. Methods: Peer-reviewed research work on spirooxindoles with antimicrobial activity were downloaded from bibliographic databases and analyzed based on their chemoptypes. Results: 50 papers were retrieved from the literature databases, of which 20 papers described the synthesis and antimicrobial activity of spirooxindoles. Conclusion: This review highlights the importance of spirooxindoles as potential antimicrobial agents. The antimicrobial activity of spirooxindoles against different types of bacteria is less studied, mainly centering on primary antimicrobial assessment, some of these compounds have showed interesting antimicrobial activity. However, the current study is only limited to primary antimicrobial assessment, no detailed modes of action are investigated.

The alarming increase of antimicrobial resistance has led to a growing number of studies aiming to develop novel antimicrobial therapeutics. Natural antimicrobial peptides possess a potent and broad-spectrum antimicrobial activity combined with diverse and unique structural motifs, which confer their different mechanisms of action. These peptides are ubiquitous in organisms and are integral to the innate immune system. Recently, identification of antimicrobial peptides from marine crustaceans has become the centre of attention of many researchers. This increasing interest stems from the remarkable diversity in the structural and genetic composition of these peptides compared to terrestrial counterparts. Thus, peptides from marine crustaceans can serve as future templates for novel antimicrobial agents. Here, we provide an overview of various antimicrobial peptides from the marine crustaceans, their antimicrobial activity and structure- activity relationships. We also discuss the potential and challenges of their development as new antimicrobial agents.

CD73, also known as ecto-5'-nucleotidase (eN, NT5E, EC3.13.5), is the ratelimiting enzyme for adenosine generation and is expressed on multiple cells. Its expression is significantly influenced by hypoxia and inflammatory factors. During inflammation, CD73 protects endothelial barrier function and inhibits leukocyte trafficking. CD73 also promotes M2 macrophages (anti-inflammatory phenotype). In addition, CD73 is expressed on Treg cells and mediates immune suppression through adenosine. CD73 serves as an essential regulator for the immunity and inflammation. Its expression is related to many diseases, such as autoimmune diseases, ischemia-reperfusion injuries, arterial calcifications, and atherosclerosis. CD73 is overexpressed in many cancers. Its expression is positively associated with tumor growth, metastasis, angiogenesis, poor prognosis and resistance to chemotherapy. Thus, CD73 may be used for prognostic indicator and therapeutic target in diseases such as cancers.

Background: Amino acids are crucially involved in a myriad of biological processes. Any aberrant changes in physiological level of amino acids often manifest in common metabolic disorders, serious neurological conditions and cardiovascular diseases. Thus, devising methods for detection of trace amounts of amino acids becomes highly elemental to their efficient clinical diagnosis. Recently, the domain of developing optical sensors for detection of amino acids has witnessed significant activity which is the focus of the current review article. Methods: We undertook a detailed search of the peer-reviewed literature that primarily deals with optical sensors for amino acids and focuses on the use of different type of materials as a sensing platform. Results: Ninety-five papers have been included in the review, majority of which deal with optical sensors. We attempt to systematically classify these contributions based on the applications of various chemical and biological scaffolds such as polymers, supramolecular assemblies, nanoparticles, DNA, heparin etc for the sensing of amino acids. This review identifies that supramolecular assemblies and nanomaterial continue to be commonly used platforms to devise sensors for amino acids followed by surfactant assemblies. Conclusion: The broad implications of amino acids in human health and diagnosis have stirred a lot of interest to develop optimized optical detection systems for amino acids in recent years, using different materials based on chemical and biological scaffolds. We have also attempted to highlight the merits and demerits of some of the noteworthy sensor systems to instigate further efforts for constructing amino acids sensor based on unconventional concepts.