SERPIN-Derived Small Peptide (SP16) as a Potential Therapeutic Agent against HIV-Induced Inflammatory Molecules and Viral Replication in Cells of the Central Nervous System.

Despite the success of combined antiretroviral therapy (cART) increasing the survival rate in human immunodeficiency virus (HIV) patients, low levels of viremia persist in the brain of patients leading to glia (microglia and astrocytes)-induced neuroinflammation and consequently, the reactivation of HIV and neuronal injury. Here, we tested the therapeutic efficacy of a Low-Density Lipoprotein Receptor-Related Protein 1 (LRP-1) agonistic small peptide drug (SP16) in attenuating HIV replication and the secretion of inflammatory molecules in brain reservoirs. SP16 was developed by Serpin Pharma and is derived from the pentapeptide sequence of the serine protease inhibitor alpha-1-antitrypsin (A1AT).

Using Extracellular Vesicles Released by GDNF-Transfected Macrophages for Therapy of Parkinson Disease.

Extracellular vesicles (EVs) are cell-derived nanoparticles that facilitate transport of proteins, lipids, and genetic material, playing important roles in intracellular communication. They have remarkable potential as non-toxic and non-immunogenic nanocarriers for drug delivery to unreachable organs and tissues, in particular, the central nervous system (CNS). Herein, we developed a novel platform based on macrophage-derived EVs to treat Parkinson disease (PD).

Different Roles of Beclin1 in the Interaction Between Glia and Neurons after Exposure to Morphine and the HIV- Trans-Activator of Transcription (Tat) Protein.

Previously we showed that Beclin1 has a regulatory role in the secretion of inflammatory molecules in glia after exposure to morphine and Tat (an HIV protein). Here we show increased secretion of neuronal growth factors and increased neuronal survival in Beclin1-deficient glia. However, without glia co-culture, neurons deficient in Beclin1 showed greater death and enhanced dendritic beading when compared to wild-type neurons, suggesting that glial-secreted growth factors compensate for the damage reduced autophagy causes neurons.

Targeting Beclin1 as an Adjunctive Therapy against HIV Using Mannosylated Polyethylenimine Nanoparticles.

Using nanoparticle-based RNA interference (RNAi), we have previously shown that silencing the host autophagic protein, Beclin1, in HIV-infected human microglia and astrocytes restricts HIV replication and its viral-associated inflammatory responses. Here, we confirmed the efficacy of Beclin1 small interfering RNA (siBeclin1) as an adjunctive antiviral and anti-inflammatory therapy in myeloid human microglia and primary human astrocytes infected with HIV, both with and without exposure to combined antiretroviral (cART) drugs. To specifically target human microglia and human astrocytes, we used a nanoparticle (NP) comprised of linear cationic polyethylenimine (PEI) conjugated with mannose (Man) and encapsulated with siBeclin1.

Impact of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the Nervous System: Implications of COVID-19 in Neurodegeneration.

Coronavirus Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome coronavirus-2 (SARS-CoV-2), began in December 2019, in Wuhan, China and was promptly declared as a pandemic by the World Health Organization (WHO). As an acute respiratory disease, COVID-19 uses the angiotensin-converting enzyme 2 (ACE2) receptor, which is the same receptor used by its predecessor, SARS-CoV, to enter and spread through the respiratory tract. Common symptoms of COVID-19 include fever, cough, fatigue and in a small population of patients, SARS-CoV-2 can cause several neurological symptoms.

Reduced-Beclin1-Expressing Mice Infected with Zika-R103451 and Viral-Associated Pathology during Pregnancy.

Here, we used a mouse model with defective autophagy to further decipher the role of Beclin1 in the infection and disease of Zika virus (ZIKV)-R103451. Hemizygous () and wild-type () pregnant mice were transiently immunocompromised using the anti-interferon alpha/beta receptor subunit 1 monoclonal antibody MAR1-5A3. Despite a low mortality rate among the infected dams, 25% of offspring were smaller in size and had smaller, underdeveloped brains.

Comparative Cytotoxicity of Inorganic Arsenite and Methylarsenite in Human Brain Cells.

The overall goal of this study is to elucidate the potential effect(s) of arsenic on a variety of human brain cells. Arsenic is the most pervasive Group A human environmental carcinogen. Long-term exposure to arsenic is associated with human diseases including cancer, cardiovascular disease, and diabetes.

GDNF-expressing macrophages restore motor functions at a severe late-stage, and produce long-term neuroprotective effects at an early-stage of Parkinson's disease in transgenic Parkin Q311X(A) mice.

There is an unmet medical need in the area of Parkinson's disease (PD) to develop novel therapeutic approaches that can stop and reverse the underlying mechanisms responsible for the neuronal death. We previously demonstrated that systemically administered autologous macrophages transfected ex vivo to produce glial cell line-derived neurotrophic factor (GDNF) readily migrate to the mouse brain with acute toxin-induced neuroinflammation and ameliorate neurodegeneration in PD mouse models. We hypothesized that the high level of cytokines due to inflammatory process attracted GDNF-expressing macrophages and ensured targeted drug delivery to the PD brain.

Morphine counteracts the antiviral effect of antiretroviral drugs and causes upregulation of p62/SQSTM1 and histone-modifying enzymes in HIV-infected astrocytes.

Accelerated neurological disorders are increasingly prominent among the HIV-infected population and are likely driven by the toxicity from long-term use of antiretroviral drugs. We explored potential side effects of antiretroviral drugs in HIV-infected primary human astrocytes and whether opioid co-exposure exacerbates the response. HIV-infected human astrocytes were exposed to the reverse transcriptase inhibitor, emtricitabine, alone or in combination with two protease inhibitors ritonavir and atazanavir (ERA) with and without morphine co-exposure.

Toll-like receptor 3 regulates Zika virus infection and associated host inflammatory response in primary human astrocytes.

The connection between Zika virus (ZIKV) and neurodevelopmental defects is widely recognized, although the mechanisms underlying the infectivity and pathology in primary human glial cells are poorly understood. Here we show that three isolated strains of ZIKV, an African strain MR766 (Uganda) and two closely related Asian strains R103451 (Honduras) and PRVABC59 (Puerto Rico) productively infect primary human astrocytes, although Asian strains showed a higher infectivity rate and increased cell death when compared to the African strain. Inhibition of AXL receptor significantly attenuated viral entry of MR766 and PRVABC59 and to a lesser extend R103451, suggesting an important role of TAM receptors in ZIKV cell entry, irrespective of lineage.

Autophagy, EVs, and Infections: A Perfect Question for a Perfect Time.

Autophagy, a highly conserved process, serves to maintain cellular homeostasis in response to an extensive variety of internal and external stimuli. The classic, or canonical, pathway of autophagy involves the coordinated degradation and recycling of intracellular components and pathogenic material. Proper regulation of autophagy is critical to maintain cellular health, as alterations in the autophagy pathway have been linked to the progression of a variety of physiological and pathological conditions in humans, namely in aging and in viral infection.

Complementary Mechanisms Potentially Involved in the Pathology of Zika Virus.

Zika virus (ZIKV) has emerged as a global health threat due to its neuro-teratogenic effect and wide range of transmission routes. Most recently, ZIKV infection has been linked with both autoimmune disorders in adults and neurodevelopmental disorders in newborns. Researchers are exploring potential cellular and molecular mechanisms underlying the neuro-teratogenicity and related consequences by using various cell culture methods and animal models.

Critical Role of Beclin1 in HIV Tat and Morphine-Induced Inflammation and Calcium Release in Glial Cells from Autophagy Deficient Mouse.

We previously showed that autophagy is an important component in human immunodeficiency virus (HIV) replication and in the combined morphine-induced neuroinflammation in human astrocytes and microglia. Here we further studied the consequences of autophagy using glial cells of mice partially lacking the essential autophagy gene Atg6 (Beclin1) exposed to HIV Tat and morphine. Tat is known to cause an inflammatory response, increase calcium release, and possibly interact with autophagy pathway proteins.

Author Correction: Intranasal drug delivery of small interfering RNA targeting Beclin1 encapsulated with polyethylenimine (PEI) in mouse brain to achieve HIV attenuation.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Importance of Autophagy in Mediating Human Immunodeficiency Virus (HIV) and Morphine-Induced Metabolic Dysfunction and Inflammation in Human Astrocytes.

Under physiological conditions, the function of astrocytes in providing brain metabolic support is compromised under pathophysiological conditions caused by human immunodeficiency virus (HIV) and opioids. Herein, we examined the role of autophagy, a lysosomal degradation pathway important for cellular homeostasis and survival, as a potential regulatory mechanism during pathophysiological conditions in primary human astrocytes. Blocking autophagy with small interfering RNA (siRNA) targeting , but not the Autophagy-related 5 () gene, caused a significant decrease in HIV and morphine-induced intracellular calcium release.

Interplay between Autophagy, Exosomes and HIV-1 Associated Neurological Disorders: New Insights for Diagnosis and Therapeutic Applications.

The autophagy-lysosomal pathway mediates a degradative process critical in the maintenance of cellular homeostasis as well as the preservation of proper organelle function by selective removal of damaged proteins and organelles. In some situations, cells remove unwanted or damaged proteins and RNAs through the release to the extracellular environment of exosomes. Since exosomes can be transferred from one cell to another, secretion of unwanted material to the extracellular environment in exosomes may have an impact, which can be beneficial or detrimental, in neighboring cells.

HIV-1 Transcription Inhibitors Increase the Synthesis of Viral Non-Coding RNA that Contribute to Latency.

Background: HIV-1 can be preserved in long-lived resting CD4+ T- and myeloid cells, forming a viral reservoir in tissues of the infected individuals. Infected patients primarily receive cART, which, to date, is the most efficient treatment against HIV/AIDS. However, the major problem in the eradication of HIV-1 from patients is the lack of therapeutic approaches to recognize the latent HIV-1 provirus and to eliminate latently infected cells.

Intranasal drug delivery of small interfering RNA targeting Beclin1 encapsulated with polyethylenimine (PEI) in mouse brain to achieve HIV attenuation.

We previously reported that activation of the host autophagic protein, Beclin1, by HIV-1 infection represents an essential mechanism in controlling HIV replication and viral-induced inflammatory responses in microglial cells. Existing antiretroviral therapeutic approaches have been limited in their ability to cross the blood-brain barrier effectively and recognize and selectively eliminate persistent HIV-infected brain reservoirs. In the present study and for the first time, the bio-distribution and efficacy of noninvasive intranasal delivery of small interfering RNA (siRNA) against the Beclin1 gene using the cationic linear polyethylenimines (PEI) as a gene carrier was investigated in adult mouse brain.

Mammalian microRNA: an important modulator of host-pathogen interactions in human viral infections.

MicroRNAs (miRNAs), which are small non-coding RNAs expressed by almost all metazoans, have key roles in the regulation of cell differentiation, organism development and gene expression. Thousands of miRNAs regulating approximately 60 % of the total human genome have been identified. They regulate genetic expression either by direct cleavage or by translational repression of the target mRNAs recognized through partial complementary base pairing.

β-Adrenergic receptor gene expression in HIV-associated neurocognitive impairment and encephalitis: implications for MOR-1K subcellular localization.

We previously reported that mRNA expression of the unique alternatively spliced OPRM1 isoform μ-opioid receptor-1K (MOR-1K), which exhibits excitatory cellular signaling, is elevated in HIV-infected individuals with combined neurocognitive impairment (NCI) and HIV encephalitis (HIVE). It has recently been shown that the β-adrenergic receptor (β-AR) chaperones MOR-1K, normally localized intracellularly, to the cell surface. Here, we found mRNA expression of the adrenoceptor beta 2 (ADRB2) gene is also elevated in NCI-HIVE individuals, as well as that β-AR protein expression is elevated in HIV-1-infected primary human astrocytes treated with morphine, and discuss the implications for MOR-1K subcellular localization in this condition.

Electro-Magnetic Nano-Particle Bound Beclin1 siRNA Crosses the Blood-Brain Barrier to Attenuate the Inflammatory Effects of HIV-1 Infection in Vitro.

The purpose of this study was to evaluate a novel drug delivery system comprised of ferric-cobalt electro-magnetic nano-material (CoFe2O4@ BaTiO3; MENP) bound to siRNA targeting Beclin1 (MENP-siBeclin1) to cross the blood-brain barrier (BBB) and attenuate the neurotoxic effects of HIV-1 infection in the central nervous system following on-demand release of siRNA using an in vitro primary human BBB model. Beclin1 is a key protein in the regulation of the autophagy pathway and we have recently demonstrated the importance of Beclin1 in regulating viral replication and viral-induced inflammation in HIV-1-infected microglia. The MENP-siBeclin1 nano-formulation did not compromise the physiological function or integrity of the BBB model.

Differing roles of autophagy in HIV-associated neurocognitive impairment and encephalitis with implications for morphine co-exposure.

We investigated the role of autophagy in HIV-infected subjects with neurocognitive impairment (NCI) ± HIV encephalitis (HIVE), many of which had a history of polysubstance abuse/dependence, using post-mortem brain tissues to determine whether differences in autophagy related factors may be more associated with NCI or NCI-encephalitis. Using qRT-PCR, we detected significant differences in gene expression levels with SQSTM1, LAMP1 higher in HIV-infected subjects without NCI while ATG5, SQSTM1 were then lower in HIV infection/NCI and ATG7, SQSTM1 being higher in NCI-HIVE. Immunohistochemical labeling of these autophagy associated proteins (also including Beclin 1 and LC3B) in Iba1-positive microglial cells showed generally higher immunoreactivity in the NCI and NCI-HIVE groups with more focal vs.