👤 W Kaye

Chronic pain and opioid use disorder (OUD) are highly prevalent and frequently co-occurring conditions that pose complex treatment challenges. While opioids are effective for pain management, prolonged use significantly enhances risk of developing substance dependence. Conversely, addiction-focused therapies often fail to relieve persistent somatic pain. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has emerged as a novel adjunctive treatment with potential to address chronic pain and substance use disorders concurrently. The present investigation examines the role of intravenous ketamine infusions in cases with coexisting chronic pain and OUD. It explores pharmacological mechanisms, therapeutic applications, clinical efficacy, and safety considerations of ketamine. Ketamine primarily acts by blocking NMDA receptors, which are central to glutamatergic signaling. This inhibition reduces neural excitability and promotes neuroplastic changes, including upregulation of brain-derived neurotrophic factor (BDNF), a protein associated with synaptic remodeling and recovery within pain and addiction pathways. These mechanisms are likely to contribute to ketamine mediated dual efficacy in managing nociceptive symptoms and reducing opioid dependence. Clinical studies suggest that ketamine may reduce pain severity, decrease opioid consumption, and alleviate withdrawal symptoms in select populations. While early evidence supports ketamine's use, its side effect profile, including dissociative symptoms, sympathomimetic activity, and potential for misuse, necessitates careful patient selection, monitoring, and oversight. Evidence remains limited by inadequate sample sizes, non-standardized protocols, and short follow-up periods. Despite these limitations, ketamine remains a promising adjunct in multimodal care, especially when conventional therapies are ineffective. Ongoing research is essential to refine protocols and to explore integration with behavioral and pharmacologic addiction interventions. Show less

Microglia, the innate immune cell of the brain, are a principal player in Alzheimer's disease (AD) pathogenesis. Their surveillance of the brain leads to interaction with the protein aggregates that drive AD pathogenesis, most notably Amyloid Beta (Aβ). Microglia attempt to clear and degrade Aβ using phagocytic machinery, spurring damaging neuroinflammation in the process. Thus, modulation of the microglial response to Aβ is crucial in mitigating AD pathophysiology. SCFAs, microbial byproducts of dietary fiber fermentation, are blood-brain barrier permeable molecules that have recently been shown to modulate microglial function. It is unclear whether propionate, one representative SCFA, has beneficial or detrimental effects on microglia in AD. Thus, we investigated its impact on microglial Aβ response in vitro. Using a multiomics approach, we characterized the transcriptomic, metabolomic, and lipidomic responses of immortalized murine microglia following 1 h of Aβ stimulation, as well as characterizing Aβ phagocytosis and secretion of reactive nitrogen species. Propionate blunted the early inflammatory response driven by Aβ, downregulating the expression of many Aβ-stimulated immune genes, including those regulating inflammation, the immune complement system, and chemotaxis. Further, it reduced the expression of Show less

Anorexia nervosa (AN) is a mental illness with high mortality that most commonly afflicts adolescent female individuals. Clinical symptoms include chronic food refusal, weight loss and body image distortions. We carried out a genome-wide association study on 1033 AN cases and 3733 pediatric control subjects, all of whom were of European ancestry and were genotyped on the Illumina HumanHap610 platform (Illumina, San Diego, CA, USA). We confirmed that common single-nucleotide polymorphisms (SNPs) within OPRD1 (rs533123, P=0.0015) confer risk for AN, and obtained suggestive evidence that common SNPs near HTR1D (rs7532266, P=0.04) confer risk for restricting-type AN specifically. However, no SNPs reached genome-wide significance in our data, whereas top association signals were detected near ZNF804B, CSRP2BP, NTNG1, AKAP6 and CDH9. In parallel, we performed genome-wide analysis on copy number variations (CNVs) using the signal intensity data from the SNP arrays. We did not find evidence that AN cases have more CNVs than control subjects, nor do they have over-representation of rare or large CNVs. However, we identified several regions with rare CNVs that were only observed in AN cases, including a recurrent 13q12 deletion (1.5 Mb) disrupting SCAS in two cases, and CNVs disrupting the CNTN6/CNTN4 region in several AN cases. In conclusion, our study suggests that both common SNPs and rare CNVs may confer genetic risk to AN. These results point to intriguing genes that await further validation in independent cohorts for confirmatory roles in AN. Show less