Polyanionic carbosilane dendrimers as a new adjuvant in combination with latency reversal agents for HIV treatment.

BACKGROUND: The major obstacle impeding human immunodeficiency virus-1 (HIV-1) eradication in antiretroviral treatment (ART) treated HIV-1 subjects is the establishment of long-lived latently infected resting CD4+ T cells. Due to the fact that no drug has been effective, the search for new drugs and combinations are a priority in the HIV cure. Treatments based on nanotechnology have emerged as an innovative and promising alternative to current and conventional therapies. In this respect, nanotechnology opens up a new door for eliminating latent HIV infection. We studied the role of G1-S4, G2-S16 and G3-S16 polyanionic carbosilane dendrimers in the context of latent HIV-1 persistence. Moreover, we study the efficiency of these dendrimers in combination with latency reversal agents (LRAs) against HIV-1 infection. METHODS: J89GFP lymphocyte and THP89GFP monocyte derived cell lines latently infected with HIV-1 p89GFP were used as an in vitro model of latency for our study. Viability assays by 3-(4-5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) were performed to determine the working concentrations of dendrimers and LRAs. Both cell lines were treated with G1-S4, G2-S16 and G3-S16 either alone or in combination with bryostatin (BRY), romidepsin (RMD) or panobinostat (PNB) for 24 and 48 h. The expression pattern of GFP was measured by flow cytometry and referred as measure of viral reactivation. RESULTS AND DISCUSSION: The combination treatment of the dendrimers with the protein kinase C (PKC) agonist did not modify the antilatency activity in J89GFP lymphocyte cell line. Interestingly enough, G3-S16 dendrimer alone and its combination with BRY, RMD or PNB showed a significant increased expression of GFP in the THP89GFP monocyte cell line. CONCLUSION: We showed for the first time that nanoparticles, in this case, G3-S16 anionic carbosilan dendrimer may play an important role in new treatments against HIV-1 infection.

VCE-004.8, A Multitarget Cannabinoquinone, Attenuates Adipogenesis and Prevents Diet-Induced Obesity.

Over the past few years, the endocannabinoid system (ECs) has emerged as a crucial player for the regulation of food intake and energy metabolism, and its pharmacological manipulation represents a novel strategy for the management of metabolic diseases. The discovery that VCE-004.8, a dual PPARγ and CB2 receptor agonist, also inhibits prolyl-hydroxylases (PHDs) and activates the HIF pathway provided a rationale to investigate its effect in in vitro models of adipogenesis and in a murine model of metabolic syndrome, all processes critically regulated by these targets of VCE-004.8. In accordance with its different binding mode to PPARγ compared to rosiglitazone (RGZ), VCE-004.8 neither induced adipogenic differentiation, nor affected osteoblastogenesis. Daily administration of VCE-004.8 (20 mg/kg) to HFD mice for 3-wks induced a significant reduction in body weight gain, total fat mass, adipocyte volume and plasma triglycerides levels. VCE-004.8 could also significantly ameliorate glucose tolerance, reduce leptin levels (a marker of adiposity) and increase adiponectin and incretins (GLP-1 and GIP) levels. Remarkably, VCE-004.8 increased the FGF21 mRNA expression in white and brown adipose, as well as in a BAT cell line, qualifying cannabinoaminoquinones as a class of novel therapeutic candidates for the management of obesity and its common metabolic co-morbidities.

VCE-004.3, a cannabidiol aminoquinone derivative, prevents bleomycin-induced skin fibrosis and inflammation through PPARγ- and CB2 receptor-dependent pathways.

BACKGROUND AND PURPOSE: The endocannabinoid system and PPARγ are important targets for the development of novel compounds against fibrotic diseases such as systemic sclerosis (SSc), also called scleroderma. The aim of this study was to characterize VCE-004.3, a novel cannabidiol derivative, and study its anti-inflammatory and anti-fibrotic activities. EXPERIMENTAL APPROACH: The binding of VCE-004.3 to CB1 and CB2 receptors and PPARγ and its effect on their functional activities were studied in vitro and in silico. Anti-fibrotic effects of VCE-004.3 were investigated in NIH-3T3 fibroblasts and human dermal fibroblasts. To assess its anti-inflammatory and anti-fibrotic efficacy in vivo, we used two complementary models of bleomycin-induced fibrosis. Its effect on ERK1/2 phosphorylation induced by IgG from SSc patients and PDGF was also investigated. KEY RESULTS: VCE-004.3 bound to and activated PPARγ and CB2 receptors and antagonized CB1 receptors. VCE-004.3 bound to an alternative site at the PPARγ ligand binding pocket. VCE-004.3 inhibited collagen gene transcription and synthesis and prevented TGFß-induced fibroblast migration and differentiation to myofibroblasts. It prevented skin fibrosis, myofibroblast differentiation and ERK1/2 phosphorylation in bleomycin-induced skin fibrosis. Furthermore, it reduced mast cell degranulation, macrophage activation, T-lymphocyte infiltration, and the expression of inflammatory and profibrotic factors. Topical application of VCE-004.3 also alleviated skin fibrosis. Finally, VCE-004.3 inhibited PDGF-BB- and SSc IgG-induced ERK1/2 activation in fibroblasts. CONCLUSIONS AND IMPLICATIONS: VCE-004.3 is a novel semisynthetic cannabidiol derivative that behaves as a dual PPARγ/CB2 agonist and CB1 receptor modulator that could be considered for the development of novel therapies against different forms of scleroderma.

Benefits of VCE-003.2, a cannabigerol quinone derivative, against inflammation-driven neuronal deterioration in experimental Parkinson's disease: possible involvement of different binding sites at the PPARγ receptor.

BACKGROUND: Neuroprotection with cannabinoids in Parkinson's disease (PD) has been afforded predominantly with antioxidant or anti-inflammatory cannabinoids. In the present study, we investigated the anti-inflammatory and neuroprotective properties of VCE-003.2, a quinone derivative of the non-psychotrophic phytocannabinoid cannabigerol (CBG), which may derive its activity at the peroxisome proliferator-activated receptor-γ (PPARγ). The compound is also an antioxidant. METHODS: We evaluated VCE-003.2 in an in vivo [mice subjected to unilateral intrastriatal injections of lipopolysaccharide (LPS)] model of PD, as well as in in vitro (LPS-exposed BV2 cells and M-213 cells treated with conditioned media generated from LPS-exposed BV2 cells) cellular models. The type of interaction of VCE-003.2 at the PPARγ receptor was furtherly investigated in bone marrow-derived human mesenchymal stem cells (MSCs) and sustained with transcriptional assays and in silico docking studies. RESULTS: VCE-003.2 has no activity at the cannabinoid receptors, a fact that we confirmed in this study using competition studies. The administration of VCE-003.2 to LPS-lesioned mice attenuated the loss of tyrosine hydroxylase (TH)-containing nigrostriatal neurons and, in particular, the intense microgliosis provoked by LPS in the substantia nigra, measured by Iba-1/Cd68 immunostaining. The analysis by qPCR of proinflammatory mediators such as tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and inducible nitric oxide synthase (iNOS) in the striatum showed they were markedly elevated by the LPS lesion and strongly reduced by the treatment with VCE-003.2. The effects of VCE-003.2 in LPS-lesioned mice implied the activation of PPARγ receptors, as they were attenuated when VCE-003.2 was co-administered with the PPARγ inhibitor T0070907. We then moved to some in vitro approaches, first to confirm the anti-inflammatory profile of VCE-003.2 in cultured BV2 cells exposed to LPS. VCE-003.2 was able to attenuate the synthesis and release of TNF-α and IL-1ß, as well as the induction of iNOS and cyclooxygenase-2 (COX-2) elicited by LPS in these cells. However, we found such effects were not reversed by GW9662, another classic PPARγ antagonist. Next, we investigated the neuroprotective effects of VCE-003.2 in cultured M-213 neuronal cells exposed to conditioned media generated from LPS-exposed cultured BV2 cells. VCE-003.2 reduced M-213 cell death, but again, such effects were not reversed by T0070907. Using docking analysis, we detected that VCE-003.2 binds both the canonical and the alternative binding sites in the PPARγ ligand-binding pocket (LBP). Functional assays further showed that T0070907 almost abolished PPARγ transcriptional activity induced by rosiglitazone (RGZ), but it did not affect the activity of VCE-003.2 in a Gal4-Luc system. However, T0070907 inhibited the effects of RGZ and VCE-003.2 on the expression of PPARγ-dependent genes upregulated in MSCs. CONCLUSIONS: We have demonstrated that VCE-003.2 is neuroprotective against inflammation-driven neuronal damage in an in vivo model of PD and in in vitro cellular models of neuroinflammation. Such effects might involve PPARγ receptors, although in silico and in vitro experiments strongly suggest that VCE-003.2 targets PPARγ by acting through two binding sites at the LBP, one that is sensitive to T0070907 (canonical binding site) and other that is not affected by this PPARγ antagonist (alternative binding site).