Preclinical to Clinical Translation of CNS Transporter Occupancy of TD-9855, a Novel Norepinephrine and Serotonin Reuptake Inhibitor

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC₅₀ of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC₅₀ values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [¹¹C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [¹¹C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC₅₀ for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.     

Commercial ‘ready‐to‐feed’ infant foods in the UK: macro‐nutrient content and composition

Quantitative analyses of the macronutrient content of eight popular commercial ‘ready‐to‐feed’ baby meals for 6–9‐month old infants in the UK market have been undertaken in order to ascertain their nutritional suitability in relation to the total daily dietary intake as well as nutritional profiling of the products. The chemical analyses conducted included Kjeldhal for protein, acid hydrolysis and extraction for fat, phenol sulphuric acid for carbohydrate and Association of Official Analytical Chemists 985.29 for fibre. The only difference found between different varieties (meat‐ and vegetable‐based) was with respect to the protein content (P = 0.04) per 100 g of food. The experimentally determined concentrations of macronutrients (g/100 kcal) were compared with the declared values provided by the manufacturers on the product labels and, despite some variations, the values obtained comply with regulatory requirements (Commission Directive 2006/125/EC). The total daily intake of fat (27.0 g per day) – based on the menu composed from commercial complementary food – is suggested to exceed the daily recommended values for fat (31%), if the intake of snacks and desserts are incorporated. These findings imply that the formulation of recipes, based on a standard commercial menu, is an important consideration in relation to the nutritional quality of the diet of infants.     

HIV Prevention and Treatment Behavior Change and the Situated Information Motivation Behavioral Skills (sIMB) Model: A Qualitative Evaluation of a Community Health Worker Intervention in Rakai,Uganda

AIDS and Behavior - A community health worker (CHW) model can promote HIV prevention and treatment behaviors, especially in highly mobile populations. In a fishing community in Rakai, Uganda, the...     

Monoclonal autoantibody from a (New Zealand black x New Zealand white)F1 mouse and some human scleroderma sera target an Mr 34,000 nucleolar protein of the U3 RNP particle

A monoclonal IgG2a antinucleolar autoantibody (72B9) was obtained by fusion of spleen cells from a (New Zealand black x New Zealand white)F1 mouse with myeloma cells (P3x63Ag8.653). Antibody 72B9 recognized a highly conserved nucleolar antigen present in both animal and plant cells. The staining pattern produced by antibody 72B9 in different cell substrates was identical with those obtained by scleroderma antibodies reactive with a basic (pI 8.5) nucleolar protein of Mr 34,000, which is associated with the U3 RNP particle. Western blotting further confirmed its reactivity with this scleroderma-related U3 RNP protein.     

Antiphospholipid antibodies in systemic lupus erythematosus: Clinical and laboratory associations in 111 patients

Summary An enzyme linked immunosorbent assay (ELISA) was used to evaluate the prevalence and disease associations of antibodies to a range of negatively charged phospholipids in 111 patients with systemic lupus erythematosus (SLE). The frequency of one or more isotypes of different antiphospholipid antibodies (APLs) was similar (range 33%–45%). When individual isotypes were considered alone there was considerable variation (range 5%–32%). There were significant associations between thrombosis, thrombocytopenia, and central nervous system (CNS) disease but not abortion with elevated APL. Strong associations were found between raised anti-ds-DNA (Farr assay) and a positive direct Coomb's test with raised APL. Thus, APLs are common in SLE and are associated with discrete clinical and laboratory features. However, detection of antibodies to a range of negatively charged phospholipids added little clinically useful information to that obtained by measuring anticardiolipin antibody (ACL) alone. We cannot recommend the use of APLs other than ACL for routine testing.     

Disseminated herpes zoster in the immunocompromised host: a comparative trial of acyclovir and vidarabine. The NIAID Collaborative Antiviral Study Group.

Seventy-three immunocompromised patients with disseminated herpes zoster were evaluated in a double-blind controlled trial of acyclovir (n = 37) versus vidarabine (n = 36) therapy. Acyclovir was administered at 30 mg/kg/day at 8-h intervals and vidarabine was given as a continuous 12-h infusion at 10 mg/kg/day for 7 days (longer if resolution of cutaneous or visceral disease was incomplete). No demographic differences existed between treatment groups. No deaths attributable to varicella-zoster virus infection occurred within 1 month of treatment. Neither rates of cutaneous healing, resolution of acute neuritis, and frequency of postherpetic neuralgia nor adverse clinical and laboratory events differed between treatment groups. Acyclovir recipients were discharged from the hospital more promptly than vidarabine recipients (P = .04, log rank test). These data indicate that disseminated herpes zoster is amenable to therapy with either acyclovir or vidarabine; resultant mortality is low.     

New Insights on the Risk for Cardiovascular Disease in African Americans: The Role of Added Sugars

African Americans are at increased risk for cardiovascular and metabolic diseases, including obesity, high BP, diabetes, CKD, myocardial infarction, and stroke. Here we summarize the current risks and provide an overview of the underlying risk factors that may account for these associations. By reviewing the relationship between cardiovascular and renal diseases and the African-American population during the early 20th century, the historic and recent associations of African heritage with cardiovascular disease, and modern population genetics, it is possible to assemble strong hypotheses for the primary underlying mechanisms driving the increased frequency of disease in African Americans. Our studies suggest that underlying genetic mechanisms may be responsible for the increased frequency of high BP and kidney disease in African Americans, with particular emphasis on the role of APOL1 polymorphisms in causing kidney disease. In contrast, the Western diet, particularly the relatively high intake of fructose-containing sugars and sweetened beverages, appears to be the dominant force driving the increased risk of diabetes, obesity, and downstream complications. Given that intake of added sugars is a remediable risk factor, we recommend clinical trials to examine the reduction of sweetened beverages as a primary means for reducing cardiovascular risk in African Americans.     

Myeloid Mixed Lineage Kinase 3 Contributes to Chronic Ethanol-Induced Inflammation and Hepatocyte Injury in Mice

Proinflammatory activity of hepatic macrophages plays a key role during progression of alcoholic liver disease (ALD). Since mixed lineage kinase 3 (MLK3)-dependent phosphorylation of JNK is involved in the activation of macrophages, we tested the hypothesis that myeloid MLK3 contributes to chronic ethanol-induced inflammatory responses in liver, leading to hepatocyte injury and cell death. Primary cultures of Kupffer cells, as well in vivo chronic ethanol feeding, were used to interrogate the role of MLK3 in the progression of liver injury. Phosphorylation of MLK3 was increased in primary cultures of Kupffer cells isolated from ethanol-fed rats compared to cells from pair-fed rats. Kupffer cells from ethanol-fed rats were more sensitive to LPS-stimulated cytokine production; this sensitization was normalized by pharmacological inhibition of MLK3. Chronic ethanol feeding to mice increased MLK3 phosphorylation robustly in F4/80⁺ Kupffer cells, as well as in isolated nonparenchymal cells. MLK3^−/− mice were protected from chronic ethanol-induced phosphorylation of MLK3 and JNK, as well as multiple indicators of liver injury, including increased ALT/AST, inflammatory cytokines, and induction of RIP3. However, ethanol-induced steatosis and hepatocyte apoptosis were not affected by MLK3. Finally, chimeric mice lacking MLK3 only in myeloid cells were also protected from chronic ethanol-induced phosphorylation of JNK, expression of inflammatory cytokines, and increased ALT/AST. MLK3 expression in myeloid cells contributes to phosphorylation of JNK, increased cytokine production, and hepatocyte injury in response to chronic ethanol. Our data suggest that myeloid MLK3 could be targeted for developing potential therapeutic strategies to suppress liver injury in ALD patients.Key words: Alcoholic liver disease (ALD), Kupffer cells, Necroptosis, Toll-like receptor 4 (TLR4), Cytokines