Current Pharmaceutical Design - Volume 23, Issue 18, 2017

Integrase strand transfer inhibitors (INSTIs) belong to a novel class of antiretroviral agents that have emerged as the new first-line treatments. Three such compounds are currently available, raltegravir, elvitegravir, dolutegravir and two more under development, bictegravir and cabotegravir. These compounds share the same mode of action but exhibit different pharmacokinetic/ pharmacodynamic properties, and drug-drug interactions. A series of studies in the past decade have established their efficacy compared to previous regimens, both in treatment- naïve and experienced patients. INSTIs have demonstrated a favorable safety profile with fewer adverse events and low rates of virological failure. Emergence of resistance to these agents, however, is a worrying concern, particularly for elvitegravir and raltegravir that display a lower genetic barrier than dolutegravir. On-going trials aim at establishing INSTIs as part of dual-drug HIV treatments or even monotherapy. New long-acting, injectable formulations are under investigation for treatment or prevention.

Background: The impact of the global economic crisis on HIV-related access and care remains unclear. The objective of this systematic review of the literature was to evaluate the association between socioeconomic factors and HIV diagnosis, and adherence to treatment, following the 2008 global economic crisis. Method: A systematic search of PubMed and Scopus for studies published between January 2008 and October 2016 was conducted. Studies providing data on social, demographic, economic and cultural barriers associated with HIV diagnosis and treatment were included. Results: Of 33 studies included, 22 evaluated HIV testing and 11 evaluated treatment adherence. Medical history of a sexually transmitted disease, knowledge of HIV-related risks, and age, were significantly associated with HIV testing in most of the included studies. Absence of social support, and alcohol or substance use, were the most common factors associated with adherence. Financial factors were not as commonly found to be related to access to HIV diagnosis and HIV treatment adherence, compared to knowledge of HIV-related risks and social support. Conclusion: The identification of persons who are less likely to test for HIV, and to adhere to HIV treatment, may serve as a guide for public health interventions, especially in resource-limited areas.

HIV remains an important public health issue worldwide. However, new prevention approaches have recently been developed and are very promising. Antiretroviral treatment as prevention, or as a prophylaxis after exposure to HIV, has been shown to reduce the likelihood of HIV acquisition. Over the last years, animal studies and randomized clinical trials in humans showed that antiretrovirals can also be efficacious and safe if used once daily, or intermittently, as prophylaxis before an individual is exposed to HIV (Pre-exposure Prophylaxis - PrEP). Fears about development of resistant strains have not been justified insofar given the accumulated evidence from research studies. Demonstration projects are ongoing and first results indicate that interests in the uptake of PrEP are high and adherence is satisfactory. Models suggest that PrEP could be a cost-effective or cost-saving approach under certain provisions including delivery to people at high risk of HIV infection, using less expensive medications, delivery in high HIV prevalence settings, short-term use for periods of higher risk, and evaluation in a longer-term period. The current review summarizes evidence on efficacy, safety and effectiveness of PrEP, and discusses future challenges and perspectives.

Cardiovascular disease is the leading cause of death worldwide. The heart is susceptible to pathologies that impact the myocardium directly, such as myocardial infarction and consequent heart failure, as well as conditions with indirect cardiac effects, such as cancer treatment-related cardiotoxicity. As the contractile cells of the heart, cardiomyocytes are essential for normal cardiac function. Various stress stimuli may result in transient damage or cell death in cardiomyocytes through apoptosis, necrosis or maladaptive autophagy. Moreover, cardiomyocytes are unable to regenerate; thus, lost cells are replaced with fibrotic tissue, with a potentially severe impact on myocardial function. Several therapeutic agents and strategies to reduce cardiomyocyte damage are currently available. This manuscript reviews the state of the art regarding novel cardioprotective endogenous peptides, such as neuregulin-1, angiotensin-(1-9), growth/differentiation factor-11, growth/differentiation factor- 15 and insulin-like growth factor-1. We discuss their protective effects and therapeutic potential in cardiovascular diseases and the current challenges to harnessing their full cardioprotective power. We also explore targeting of exosomes as a cardioprotective approach along with the therapeutic potential of cardiac regeneration strategies. Further advances associated with these molecules and cardioprotective approaches may provide more effective therapies to attenuate or prevent cardiomyocyte death, thereby preserving the myocardium.

Influenza A virus is one of the major human pathogens. The influenza infection can pass out without any subclinical symptoms or infestation can appear in upper respiratory tract as well as in lower respiratory tract where it can result in lethal outcome. Both innate and adaptive immune responses are activated shortly after infection providing protection against infection. Many activities of the cells of innate and adaptive immunity are coordinated by cytokines. However, inordinate or disbalanced immune response may result in overproduction of cytokines as well as chemokines which can lead to severe inflammation, including excessive recruitment of neutrophils and mononuclear cells at the site of infection. These may damage lung tissue, reduce respiratory capacity, and cause severe disease and mortality. Recently, the role of cytokines induced by virus infection has been reevaluated. While moderate inflammatory response protects against development of severe illness, the hyper-inflammatory response can elevate the disease progression. In this mini-review, we summarized the data on cytokines and chemokines induced in the sera of hospitalized patients infected with human and avian influenza viruses and define their possible role in pathogenesis. Interleukin IL-6 and chemokines CCL-2/MCP-1, CCL-4/MIP-1β, CXCL-8/IL-8, CXCL-9/MIG, and CXCL-10/IP-10 are associated with pathogenicity of both avian (H5N1 and H7N9) and human (pdmH1N1 and H3N2) viruses. Chemokines CCL-2/MCP-1, CXCL-8/IL-8, CXCL-9/MIG, and CXCL-10/IP-10 are also related with mortality. These cytokines may be used as targets for new, more complex therapy in the extenuation of unfavorable effects of hyper inflammatory response.

Cell-based tolerogenic therapy is a promising approach for the treatment of autoimmune diseases and transplant rejection. Regulatory T cells and tolerogenic dendritic cells have been particularly explored in the treatment of various autoimmune disorders in experimental models of disease. Although some of these cells have already been tested in a limited number of clinical trials, there is still a need for preclinical research on tolerogenic cells in animal models of autoimmunity. This review will focus on the relevance of data obtained from studies in experimental animal models for the use of tolerogenic cell-based therapy in humans. Also, perspectives for further improvement of tolerogenic cell preparation towards enhanced suppressive activity and stability of the cells will be discussed.

The high incidence of tuberculosis (TB) in the world, especially in developing countries, the resurgence of TB in industrialized countries, and the global increase in the prevalence of Mycobacterium avium complex infections in immunocompromised hosts have prompted the quest for novel antimycobacterial drugs. However, the development of such antimicrobial chemotherapeutics is currently making very slow progress even with using the bioinformatics-based methodology for drug design. It thus appears that devising improved administration protocols for clinical treatment against intractable mycobacterial infections using existing chemotherapeutics is more practical than awaiting the development of new antimycobacterial drugs. The potentiation of host immune responses using immunoadjunctive agents, alternatively called host-directed therapeutics (HDTs), may increase the efficacy of antimycobacterial regimens against mycobacteriosis. Particularly, the modulation of host immunity relating to macrophage antimicrobial functions may be beneficial to the immunoadjunctive therapy. This review will deal with the current status and future prospects regarding the development of HDTs useful for the clinical control of intractable mycobacterial infections.

Background:Heme Oxygenase-1 (HO-1) is a metabolic enzyme strongly involved in processes including cytoprotection, modulation of inflammatory response, anti-oxidative functions, regulation of cellular proliferation, angiogenesis, cardiovascular homeostasis, and immuno-modulation. HO-1 induction and/or activation is able to counterbalance, at least in part, oxidative stress and inflammation. For this reason, HO-1 can be regarded as an attractive target to ameliorate different stress-related pathologies. Caffeic acid phenethyl ester, a natural polyphenolic compound, behaves as HO-1 inducer and possesses a plethora of beneficial effects under oxidative stress conditions. Objectives: A small focused series of caffeic acid phenethyl ester (Cape) analogues was designed and synthesized with the aim of obtaining more potent HO-1 inducers. Method: The capacity of these new compounds to modify the levels of HO-1 was evaluated in human mesenchymal stem cells (hMSCs) derived from bone marrow. Results and conclusion: Some of tested compounds were found to be good HO-1 inducers and 3-(3,4- dihydroxyphenyl)-(2E)-2-propenoic acid 2-(3,4-dimethoxyphenyl) ethyl ester (VP961) was the most potent. VP961 tested to measure HO-1 protein expression and HO activity in in vitro system resulted more potent than the parent compound Cape both as inducer and as direct activator of the enzyme. VP961, selected as lead compound for further characterization, showed antioxidant properties in a model of H2O2-mediated ROS production and cytoprotective effects in a model of H2O2 cells viability impairment. To the best of our knowledge, VP961 is the first known compound able to activate directly HO-1 enzyme and to induce at the same time its protein expression.

There is no doubt about the whole cell pertussis vaccine efficacy, but it is necessary to improve the vaccine quality specially to decrease its toxicity by obtaining good immunogenicity with low bacterial content. In this work, under optimum condition inactivated B. pertussis bacteria cells entrapped with alginate microparticles were fabricated and in vivo immunogenicity and ptency of new microparticle based vaccine were evaluated in mice. Microspheres loaded with inactive B. pertussis bacterium cells were prepared via an emulsification method and analyzed for morphology, size, polydispersity index, loading efficiency, loading capacity, release profile and in vivo potency. The inactivated bacterial suspension mixture prepared in this work was nontoxic and showed potent ED50 (1:333 of human dose) and preserved agglutinins 1, 2, 3. The optimum conditions for the preparation of microparticles were achieved at alginate concentration 3.8% (w/v), CaCl2 8% (w/v), PLL 0.1% (w/v), lipophilic surfactant 0.22 (%w/v), hydrophilic surfactant 3.6 (%w/v), cross linking time 3min, homogenization rate 600 rpm, and alginate to CaCl2 solution ratio 4. Both empty and B. pertussis loaded microparticles exhibited smooth surface texture and relatively spherical shape. The B. pertussis encapsulated microspheres fabricated under optimized conditions showed mean particle size 151.1 μm, polydispersity index 0.43, loading efficiency 89.6%, loading capacity 36.3%, and relatively constant release rate lasted to 15 days. In vivo immunogenicity and protection study against wild type challenge showed strongly higher potency (approximately 2.5 fold) of encapsulated B. pertussis organisms than non-encapsulated conventional aluminum hydroxide adsorbed vaccine. It can be concluded that microencapsulation of inactive B. pertussis cells appears to be a suitable approach for improving the wP vaccine quality, specially by obtaining good immunogenicity with low bacterial content.

Parkinsonian-like state was generated in mice by the administration of 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP) to study the effects of Atremorine in Parkinson's disease (PD) related neuropathology and behavior deficits. This devastating disease is caused by the progressive degeneration of dopaminergic neurons in the substantia nigra. Numerous therapeutic strategies have been developed to protect neuronal damage, although no effective treatment for PD has been validated yet. This study tested the preventive and therapeutic neuroprotective effect of Atremorine on MPTP parkinsonian mouse model. In addition to behavioral analysis, nigrostriatal dopaminergic neurons and inflammation biomarkers were directly quantified in the affected brain regions by specific antibody-antigen-binding methods. The affected neuronal populations and behavioural alterations induced by MPTP were significantly impaired in mice when treated with Atremorine-rich diet. Differences in the Atremorine content in diet induced some degrees of neuropathological and behavior therapeutical improvement, based on the progressive beneficial effects observed in nigro-striatal dopaminergic neurons of MPTPinduced mice. Data demonstrated that Atremorine promotes neuroprotection and behavior recovery in the injured MTPT-mouse brain by modulating the expression levels of tyrosine hydroxylase, glial proteins, apoptosis and endogenous dopamine and neuromelanin concentrations, probably the key to recover the basal ganglia function.

Background: Light delivery in photodynamic therapy is a challenging issue in deep cancer treatment. To solve this problem, photosensitizers are conjugated to X-ray luminescent nanoparticles. When the complexes are stimulated by X-rays during radiotherapy, the nanoparticles generate light and activate the photosensitizers. Method: Core-shell molecularly imprinted polymers (MIPs) were prepared against mitoxantrone (MX) in which TiO2 nanoparticles were applied as a core, diacrylated polycaprolctone as a biodegradable cross-linker and methacrylic acid (MAA) or 4-vinylpyridin (4-VP) as the functional monomer. TiO2 was selected as a scintillator, MX as a photosensitizer and MIP as a drug delivery system in order to evaluate the possibility of using photodynamic therapy (PDT) during radiotherapy in the next studies. Binding properties of polymers and drug release profile were studied and the optimized MIP was characterized by SEM, TEM, EDS, FT-IR and XRD. Also, cytotoxicity and free radical production were also studied in vitro. Results: Data indicated that MAA-based MIP had superior binding properties compared to its non-imprinted polymer (NIP) and higher imprinting factor value than MIP-4VP. Drug release experiments indicated higher MX released amount from MAA-based MIP than the other polymers. MAA-based MIP was selected as an optimized carrier for MX delivery system. According to the results, the size of MX-MIP@TiO2 was reported to be less than 75 nm. The free radical production and cytotoxicity of nanoparticles were also evaluated in vitro. Conclusion: The results of the present work proposed the possibility of applying MIP layer as a drug delivery system around TiO2 nanoparticles.