👤 M Kuan

Neurodegenerative diseases such as Alzheimer's (AD), Parkinson's (PD), Huntington's (HD), and multiple sclerosis (MS) involve progressive neuronal loss driven by dysregulated neurotransmission, neuroinflammation, oxidative stress, and mitochondrial dysfunction. Cholesterol metabolism has emerged as a critical factor involved with both central and peripheral dysregulation contributing to pathology. This review synthesizes current evidence on cholesterol's role in neurodegeneration and evaluates the therapeutic potential of statins, which act via cholesterol-dependent and other pleiotropic mechanisms. A PubMed search covering 1985-2025 publications was conducted using terms related to neurodegenerative diseases, statins, cholesterol metabolism, neuroinflammation, oxidative stress, mitochondrial dysfunction, and neuroprotection. Studies were selected to highlight mechanistic insights into cholesterol regulation in the nervous system and clinical data on statin use. Neuronal loss in neurodegeneration is driven by processes including excitotoxicity, inflammation, and mitochondrial dysfunction. Excessive reactive oxygen species activate apoptotic pathways involving Show less

Women with autoimmune diseases (AIDs) experience chronic immune dysregulation and hormonal fluctuations, both of which may influence breast cancer risk. However, it remains unclear whether this risk is driven mainly by its treatment or the underlying disease, highlighting the need for integrating real-world data and genetic evidence. The FDA Adverse Event Reporting System (FAERS) were utilized to identify breast cancer safety signals among women with AIDs, analyzing 11,479 reports from 2004 to 2024. Disproportionality analyses using Reporting Odds Ratio (ROR) and Information Component (IC) were conducted. Then, we mapped these drugs to their target genes and performed mendelian randomization (MR) to assess their causal relationships with breast cancer. Finally, we investigated shared genetic architecture between breast cancer and AIDs using global and local genetic correlation, cross-trait meta-analysis, and transcriptome-wide association studies. We identified 13 immunosuppressive drugs (TNF inhibitors, interleukin inhibitors, and monoclonal antibodies), 3 immunostimulants and 16 adjunctive drugs associated with increased breast cancer reporting in patients with AIDs. The drugs with the highest case reports for positive disproportionality analysis were interferon beta-1a (N: 1731, IC [IC025] 1.56 [1.49]), natalizumab (798, 0.65 [0.54]), and infliximab (741, 0.64 [0.53]). MR results revealed causal links between 9 drug targets and breast cancer risk, such as FDPS (OR: 0.66, p: 1.33E-08), CALCRL (OR: 0.887, p: 4.77E-06) and PARP1 (OR: 1.051, p: 3.50E-06). Global genetic correlation identified significant shared heritability between breast cancer and 3 specific AIDs, including type 1 diabetes mellitus (rg: -0.242, p: 0.95E-4), ulcerative colitis (rg: 0.125, p: 0.29E-2), and migraine (rg: 0.078, p: 0.79E-2). Specifically, the most notable genetic overlap was observed between breast cancer and type 1 diabetes mellitus, with significant shared risk SNPs (rs12046289 and rs6679677) and susceptibility genes (ADCY3 and CENPO). Our study uncovered several immune-related drugs associated with increased breast cancer reporting in women with AIDs. This risk may be explained by several potential drug targets with causal roles, or by the shared genetic comorbidity between specific AIDs and breast cancer. These insights emphasize the need for tailored breast cancer surveillance and highlight potential molecular targets for intervention in vulnerable populations. Show less

Protein activities controlled by receptor protein tyrosine phosphatases (RPTPs) play comparably important roles in transducing cell surface signals into the cytoplasm by protein tyrosine kinases. Previous studies showed that several RPTPs are involved in neuronal generation, migration, and axon guidance in Drosophila, and the vertebrate hippocampus, retina, and developing limbs. However, whether the protein tyrosine phosphatase type O (ptpro), one kind of RPTP, participates in regulating vertebrate brain development is largely unknown. We isolated the zebrafish ptpro gene and found that its transcripts are primarily expressed in the embryonic and adult central nervous system. Depletion of zebrafish embryonic Ptpro by antisense morpholino oligonucleotide knockdown resulted in prominent defects in the forebrain and cerebellum, and the injected larvae died on the 4th day post-fertilization (dpf). We further investigated the function of ptpro in cerebellar development and found that the expression of ephrin-A5b (efnA5b), a Fgf signaling induced cerebellum patterning factor, was decreased while the expression of dusp6, a negative-feedback gene of Fgf signaling in the midbrain-hindbrain boundary region, was notably induced in ptpro morphants. Further analyses demonstrated that cerebellar defects of ptpro morphants were partially rescued by inhibiting Fgf signaling. Moreover, Ptpro physically interacted with the Fgf receptor 1a (Fgfr1a) and dephosphorylated Fgfr1a in a dose-dependant manner. Therefore, our findings demonstrate that Ptpro activity is required for patterning the zebrafish embryonic brain. Specifically, Ptpro regulates cerebellar formation during zebrafish development through modulating Fgf signaling. Show less

Hypertrophic cardiomyopathy (HCM) is a common form of cardiac disease. Over 400 causative mutations have been identified in 20 sarcomere and myofilament related genes. The high density of mutations found in genes associated with HCM may suggest that mechanisms promoting increased mutability play a role in disease prevalence. The objective of this study was to evaluate the CpG methylation level of the exonic regions of the cardiac myosin binding protein C gene (MYBPC3), a common causal gene for HCM. To determine if the methylation level is gene specific and possibly involved with gene mutability, we also evaluated the methylation of the CpGs within the exonic regions of the skeletal muscle isoform of the myosin binding protein C gene (MYBPC2); there are no known mutations that lead to the development of familial human disease within this gene. We determined that although the mean number of CG sites was identical within the coding region of each gene, the mean methylation level of CpGs was significantly higher in MYBPC3 than MYBPC2 (P < 0.0001). The results of this study suggest that there are unique aspects of this cardiac gene or its epigenetic environment which may result in increased genetic mutability. Evaluation of the methylation levels of additional causal cardiomyopathic genes is warranted. Show less

Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats. Causative mutations have been identified in the Maine Coon (MC) and Ragdoll breed in the cardiac myosin binding protein C gene (MYBPC3). HCM is thought to be inherited in other breeds. That a causative mutation for HCM in the British Shorthair (BSH), Norwegian Forest (NWF), Siberian, Sphynx, or MC cats would be identified in the exonic and splice site regions of 1 of 8 genes associated with human familial HCM. Three affected BSH, NWF, Siberians, Sphynx, 2 MC (without the known MC mutation), and 2 Domestic Shorthair cats (controls) were studied. Prospective, observational study. Exonic and splice site regions of the genes encoding the proteins cardiac troponin I, troponin T, MYBPC3, cardiac essential myosin light chain, cardiac regulatory myosin light chain, alpha tropomyosin, actin, and beta-myosin heavy chain were sequenced. Sequences were compared for nucleotide changes between affected cats, the published DNA sequences, and control cats. Changes were considered to be causative for HCM if they involved a conserved amino acid and changed the amino acid to a different polarity, acid-base status, or structure. A causative mutation for HCM was not identified, although several single nucleotide polymorphisms were detected. Mutations within these cardiac genes do not appear to be the only cause of HCM in these breeds. Evaluation of additional cardiac genes is warranted to identify additional molecular causes of this feline cardiac disease. Show less