JOTROL, a Novel Formulation of Resveratrol, Shows Beneficial Effects in the 3xTg-AD Mouse Model

Background: Alzheimer’s disease (AD) has minimally effective treatments currently. High concentrations of resveratrol, a polyphenol antioxidant found in plants, have been reported to affect several AD-related and neuroprotective genes. To address the low bioavailability of resveratrol, we investigated a novel oral formulation of resveratrol, JOTROLTM, that has shown increased pharmacokinetic properties compared to non-formulated resveratrol in animals and in humans. Objective: We hypothesized that equivalent doses of JOTROL, compared to non-formulated resveratrol, would result in greater brain exposure to resveratrol, and more efficacious responses on AD biomarkers. Methods: For sub-chronic reversal studies, 15-month-old male triple transgenic (APPSW/PS1M146V/TauP301L; 3xTg-AD) AD mice were treated orally with vehicle or 50 mg/kg JOTROL for 36 days. For prophylactic studies, male and female 3xTg-AD mice were similarly administered vehicle, 50 mg/kg JOTROL, or 50 mg/kg resveratrol for 9 months starting at 4 months of age. A behavioral battery was run, and mRNA and protein from brain and blood were analyzed for changes in AD-related gene and protein expression. Results: JOTROL displays significantly increased bioavailability over non-formulated resveratrol. Treatment with JOTROL resulted in AD-related gene expression changes (Adam10, Bace1, Bdnf, Psen1) some of which were brain region-dependent and sex-specific, as well as changes in inflammatory gene and cytokine levels. Conclusion: JOTROL may be effective as a prophylaxis and/or treatment for AD through increased expression and/or activation of neuroprotective genes, suppression of pro-inflammatory genes, and regulation of central and peripheral cytokine levels.

β-Amyloid is an Immunopeptide and Alzheimer's is an Autoimmune Disease

Background: As new biomolecular targets for Alzheimer’s disease (AD) emerge, there is a tendency to regard these as mutually exclusive and in competition, culminating in declarations that since the “amyloid hypothesis is dead” it needs to be replaced by completely different theories. However, given the well-described role of misfolding peptides, particularly β-amyloid (Aβ), in the pathogenesis of AD, the need for a broad-based conceptualization of AD, coalescing different theories into a single harmonized explanation emerges as a viable alternative. Incorporating protein aggregation mechanisms of AD into a more widely-encompassing immunopathic model of AD could accomplish such a goal – a goal which could be achieved by repositioning the role of Aβ as an immunopeptide. Conclusions: This review presents the concept that Aβ is an immunopeptide and that AD is an autoimmune disease in which Aβ is a key molecular player. Being a peptide with the capacity to alter immune function, Aβ is an immunopeptide; having both antimicrobial and immunomodulatory activities, Aβ is a host defense peptide; having most of the defining properties of cytokines, Aβ satisfies the broad definition of cytokine – the prototypic immunopeptide subtype. In addition to these immunoactivities, Aβ is also directly and independently cytotoxic to neurons by both necrotic and apoptotic mechanisms. Therefore, following brain exposure to immune-instigating stimuli, the innate immune system is activated, leading to the release of Aβ as an immunopeptide (functioning as a host defense peptide or cytokine), which subsequently inflicts a misdirected attack upon the host neurons – an autoimmune event.

Discovery of HBW-3-20, the first potent reversible inhibitor of Bruton’s tyrosine kinase (BTK) with high brain exposure.

e15068 Background: It has been an on-demand task to develop a BTK inhibitor of significant brain exposure, a critical property for extending its usages to treat Primary Central Nervous System Lymphoma (PCNSL) and autoimmune disorders. PCNSL is an aggressive extra nodal non-Hodgkin lymphoma that exclusively invades the central nervous system (CNS). Tirabrutinib, an irreversible BTK inhibitor with limited brain exposure, is the first BTK inhibitor approved for the treatment of recurrent or refractory primary central nervous system lymphoma recently. PRN2246 is another irreversible BTK inhibitor claimed to be of brain exposure, and is currently in clinical trials for the treatment of multiple sclerosis. Methods: New reversible BTK inhibitors were designed, synthesized and tested for enzymatic activities against wild-type and C481S-mutated BTK. Highly active compounds were confirmed for growth effects in diffuse large B-cell lymphoma derived TMD8 cells. Their microsomal stability and ADME properties were also assessed. Potent and bioavailable compounds were further measured for brain exposures in rats. Results: HBW-3-20 has excellent potency against both wild-type and C481S-mutated BTK, with IC50 of 2.5 and 3.8 nM, respectively. Its TMD8 cellular potency is 72 nM. In a head-to-head direct comparison of brain exposure experiment, HBW-3-20, tirabrutinib and PRN2246 were all dosed at 10mg/kg orally. The brain and plasma concentration were measured after 1 hour and the data are shown in the table below. The brain to plasma ratio for HBW-3-20, tirabrutinib and PRN2246 are 58%, 11.8% and 4.2% respectively. Our results show that HBW-3-20 has much greater brain permeability than tirabrutinib or PRN2246 in rats. Conclusions: HBW-3-20 is the first potent reversible BTK inhibitor that shows promisingly high brain permeability. HBW-3-20 provides a very valuable clinical candidate for treating B-cell malignancies in brain and autoimmune disorders![Table: see text]

Regulation of Drosophila Long-Term Courtship Memory by Ecdysis Triggering Hormone

Endocrine state is an important determinant of learning and memory in animals. InDrosophila, rejection of male courtship overtures by mated females leads to an aversive response manifested as courtship memory. Here we report that ecdysis triggering hormone (ETH) is an obligatory enabler of long-term courtship memory (LTM). ETH deficiency suppresses LTM, whereas augmented ETH release reduces the minimum training period required for LTM induction. ETH receptor knockdown either in the mushroom body (MB) γ lobe or in octopaminergic dorsal-anterior-lateral (DAL) neurons impairs memory performance, indicating its direct action in these brain areas. Consistent with these findings, brain exposure to ETH mobilizes calcium in MB γ lobe neuropils and DAL neurons. ETH receptor (ETHR) knockdown in the corpus allatum (CA) to create juvenile hormone (JH) deficiency also suppresses LTM, as does knockdown of the JH receptor Met in the MB γ lobe, indicating a convergence of ETH and JH signaling in this region of the brain. Our findings identify endocrine-enabled neural circuit components in the brain that are critical for persistent behavioral changes resulting from aversive social experience.

Quantification and Metabolite Identification of Sulfasalazine in Mouse Brain and Plasma Using Quadrupole-Time-of-Flight Mass Spectrometry

Sulfasalazine (SAS), an anti-inflammatory drug with potent cysteine/glutamate antiporter system xc-(SXC) inhibition has recently shown beneficial effects in brain-related diseases. Despite many reports related to central nervous system (CNS) effect of SAS, pharmacokinetics (PK) and metabolite identification studies in the brain for SAS were quite limited. The aim of this study was to investigate the pharmacokinetics and metabolite identification of SAS and their distributions in mouse brain. Using in vivo brain exposure studies (neuro PK), the PK parameters of SAS was calculated for plasma as well as brain following intravenous and oral administration at 10 mg/kg and 50 mg/kg in mouse, respectively. In addition, in vivo metabolite identification (MetID) studies of SAS in plasma and brain were also conducted. The concentration of SAS in brain was much lower than that in plasma and only 1.26% of SAS was detected in mouse brain when compared to the SAS concentration in plasma (brain to plasma ratio (%): 1.26). In the MetID study, sulfapyridine (SP), hydroxy-sulfapyridine (SP-OH), and N-acetyl sulfapyridine (Ac-SP) were identified in plasma, whereas only SP and Ac-SP were identified as significant metabolites in brain. As a conclusion, our results suggest that the metabolites of SAS such as SP and Ac-SP might be responsible for the pharmacological effect in brain, not the SAS itself.