Sex hormone-binding globulin (SHBG), which regulates androgen and estrogen bioavailability, has been linked to cognitive decline, but its relationship with temporal lobe changes-an area vulnerable in Show more
Sex hormone-binding globulin (SHBG), which regulates androgen and estrogen bioavailability, has been linked to cognitive decline, but its relationship with temporal lobe changes-an area vulnerable in early Alzheimer's disease (AD)-remains unclear. This study aimed to investigate whether plasma SHBG levels are associated with temporal lobe volume and cognitive performance across the cognitive spectrum from normal aging to AD. Participants included individuals with AD (n = 85), mild cognitive impairment (MCI; n = 304), and cognitively normal controls (CN; n = 50). Cognitive performance was assessed using the ADAS-Cog 11, MMSE, and CDR-SB. Temporal lobe volumes were derived from MRI scans using tensor-based morphometry (TBM), and plasma SHBG levels were measured using a validated immunoassay. Multiple regression analyses adjusted for age, sex, education, handedness, and APOE ε4 status were conducted, followed by mediation analysis to test indirect effects through temporal lobe volume. After covariate adjustment, elevated plasma SHBG levels were significantly associated with reduced temporal lobe volume in the MCI group. Across both MCI and AD participants, greater temporal lobe volume correlated with better cognitive performance on all tests. Mediation analysis indicated that in MCI, the relationship between higher plasma SHBG and poorer cognitive outcomes was significantly mediated by reduced temporal lobe volume. These findings suggest that elevated SHBG may contribute to early cognitive impairment in MCI through its impact on temporal lobe integrity, highlighting SHBG as a potential target in the prodromal stages of AD. Show less
The hallmark of Alzheimer's disease (AD), a progressive neurodegenerative condition, is the buildup of amyloid-beta (Aβ) plaque, which is mainly caused by β-secretase 1 (BACE-1) activity. BACE-1 inhib Show more
The hallmark of Alzheimer's disease (AD), a progressive neurodegenerative condition, is the buildup of amyloid-beta (Aβ) plaque, which is mainly caused by β-secretase 1 (BACE-1) activity. BACE-1 inhibition is a potentially effective treatment strategy to lower the progression of AD. In order to find possible BACE-1 inhibitors using a drug repurposing technique, this study uses an integrated computational approach that includes pharmacophore modelling, virtual screening, molecular docking, MM-GBSA, molecular dynamics (MD) simulations, in-silico ADMET profiling, and PBPK modelling. A pharmacophore model, was created with known BACE-1 inhibitors to enable virtual screening of both novel and FDA-approved chemical libraries. Top candidates with good free energy scores and strong binding affinities were found using molecular docking and MM-GBSA calculations. The stability of shortlisted Hits inside the BACE-1 active site was further validated using MD simulations, which showed that some of the important interactions were maintained across a period of 50ns. ADMET and PBPK studies predicted favorable pharmacokinetic and safety profiles for the shortlisted hits, particularly for B2 and B9. These findings identify potential candidates for future experimental validation, offering an inexpensive approach for identification of compounds as potential BACE-1 inhibitors. Show less