Long-COVID impacts taste and olfactory in individuals with substance use disorder: A retrospective cohort study from the TriNetX US Collaborative Networks.

Substance use disorder (SUD) exacerbates the impact of Long-COVID, particularly increasing the risk of taste and olfactory disorders. Analyzing retrospective cohort data from TriNetX and over 33 million records (Jan 2020-Dec 2022), this study focused on 1,512,358 participants, revealing that SUD significantly heightens the likelihood of experiencing taste disturbances and anosmia in Long-COVID sufferers. Results indicated that individuals with SUD face a higher incidence of sensory impairments compared to controls, with older adults and women being particularly vulnerable. Smokers with SUD were found to have an increased risk of olfactory and taste dysfunctions. The findings underscore the importance of early screening, diagnosis, and interventions for Long-COVID patients with a history of SUD, suggesting a need for clinicians to monitor for depression and anxiety linked to sensory dysfunction for comprehensive care.

Small intestine submucosa as a growth factor attractor promotes peripheral nerve regeneration by enhancing syndecan-3/glial cell line-derived neurotrophic factor (GDNF) signalling:in vivostudy.

Peripheral nerve regeneration (PNR) following trauma requires the reconstruction of the extracellular matrix (ECM) and the proper stimulation of growth factors. Decellularised small intestine submucosa (SIS) has been extensively used as an ECM scaffold for tissue repair, but its potential to enhance the effects of exogenous growth factors on PNR is not well understood. In this study, we evaluated the effects of SIS implantation combined with glial cell-derived growth factor (GDNF) treatment on PNR in a rat neurorrhaphy model. We found that both SIS and regenerating nerve tissue expressed syndecan-3 (SDC3), one of major heparan sulphate proteoglycans in nerve tissue, and that SDC3 interacted with GDNF in the regenerating nerve tissue. Importantly, the SIS-GDNF combined treatment enhanced the recovery of neuromuscular function andß3-tubulin-positive axonal outgrowth, indicating an increase in the number of functioning motor axons connecting to the muscle after neurorrhaphy. Our findings suggest that the SIS membrane offers a new microenvironment for neural tissue and promotes neural regeneration based on SDC3-GDNF signalling, providing a potential therapeutic approach for PNR.