👤 Thomas K Karikari

Lithium deficiency may contribute to Alzheimer disease pathogenesis. No randomized clinical trial has examined lithium's effects on cognition, neuroimaging, and plasma biomarkers in mild cognitive impairment (MCI). To examine the feasibility, safety, and preliminary efficacy of lithium carbonate for delaying cognitive decline in older adults with MCI. This single-site, randomized, double-blind, placebo-controlled pilot feasibility clinical trial was conducted at the University of Pittsburgh School of Medicine from February 2018 to August 2024, with 2-year follow-up. Analyses used linear mixed-effects models in the intention-to-treat population. Adults aged 60 years or older with MCI who were free of major psychiatric or neurologic illness and contraindications to lithium were included. Of 170 individuals assessed, 83 were randomized (41 lithium vs 42 placebo), with 80 starting treatment (41 lithium vs 39 placebo). Data were analyzed from August 2024 to December 2025. Daily low-dose lithium carbonate or placebo for 2 years. Six prespecified coprimary outcomes included cognitive performance (California Verbal Learning Test-II [CVLT-II] delayed recall, Brief Visuospatial Memory Test-Revised, preclinical Alzheimer cognitive composite), hippocampal volume, cortical gray matter volume, and brain-derived neurotrophic factor. Among 80 participants (mean [SD] age, lithium: 72.93 [8.77] years; placebo: 71.22 [6.47] years; 56% female), none of the 6 coprimary outcomes met the prespecified significance threshold. Mean (SD) CVLT-II baseline scores were 7.95 (3.4) for lithium and 7.90 (3.9) for placebo; scores declined 1.42 points annually in the placebo group vs 0.73 points in the lithium group (difference, 0.69 points per year; 95% CI, 0.01-1.37; P = .05). Hippocampal and cortical volumes showed a decline over time in both groups, but no significant treatment × time interactions. Serious adverse events occurred in 12 of 41 (29%) receiving lithium vs 9 of 39 (23%) receiving placebo; none were definitely treatment related. One death occurred in the placebo group. Common adverse events included increased creatinine levels (12 of 41 [29%] with lithium vs 12 of 39 [31%] with placebo), diarrhea (12 of 41 [29%] vs 6 of 39 [15%]), tiredness (12 of 41 [29%] vs 6 of 39 [15%]), and tremor occurrence (10 of 41 [24%] vs 6 of 39 [15%]). This pilot randomized clinical trial established feasibility, confirmed safety and tolerability, and generated effect size estimates for future trials of low-dose lithium in MCI. None of the coprimary outcomes met the prespecified significance threshold. ClinicalTrials.gov Identifier: NCT03185208. Show less

Multiple genome-wide association studies (GWAS) have identified SNPs in the 8q24 locus near TRIB1 that are significantly associated with plasma lipids and other markers of cardiometabolic health, and prior studies have revealed the roles of hepatic and myeloid Trib1 in plasma lipid regulation and atherosclerosis. The same 8q24 SNPs are additionally associated with plasma adiponectin levels in humans, implicating TRIB1 in adipocyte biology. Here, we hypothesize that TRIB1 in adipose tissue regulates plasma adiponectin, lipids, and metabolic health. We investigate the metabolic phenotype of adipocyte-specific Trib1 knockout mice (Trib1_ASKO) fed on chow and high-fat diet (HFD). Through secretomics of adipose tissue explants and RNA-seq of adipocytes and livers from these mice, we further investigate the mechanism of TRIB1 in adipose tissue. Trib1_ASKO mice have an improved metabolic phenotype with increased plasma adiponectin levels, improved glucose tolerance, and decreased plasma lipids. Trib1_ASKO adipocytes have increased adiponectin production and secretion independent of the known TRIB1 function of regulating proteasomal degradation. RNA-seq analysis of adipocytes and livers from Trib1_ASKO mice indicates that alterations in adipocyte function underlie the observed plasma lipid changes. Adipose tissue explant secretomics further reveals that Trib1_ASKO adipose tissue has decreased ANGPTL4 production, and we demonstrate an accompanying increase in the lipoprotein lipase (LPL) activity that likely underlies the triglyceride phenotype. This study shows that adipocyte Trib1 regulates multiple aspects of metabolic health, confirming previously observed genetic associations in humans and shedding light on the further mechanisms by which TRIB1 regulates plasma lipids and metabolic health. Show less