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Assessment of CFH and HTRA1 polymorphisms in age-related macular degeneration using classic and machine-learning approaches

2020 , Martínez Velasco, Antonieta Teodora , Pérez Ortiz, Andric Christopher , Antonio-Aguirre, Bani , Martinez-Villaseñor, Lourdes , Palacio-Pastrana, Claudia , Lira, Esmeralda , Zenteno, Juan Carlos , Ramírez-Sánchez, Israel , Zepeda-Palacio, Claudia , Mendoza Vera, Cristina Azucena , Camacho-Ordóñez, Azyadeh , Ortiz Bibriesca, Daniela , Estrada Mena, Francisco Javier

CFH: and HTRA1 are pivotal genes driving increased risk for age-related macular degeneration (AMD) among several populations. Here, we performed a hospital-based case-control study to evaluate the effects of three single nucleotide polymorphisms (SNPs) among Hispanics from Mexico. Materials and methods: 122 cases and 249 controls were genotyped using Taqman probes. Experienced ophthalmologists diagnosed AMD following the American Association of Ophthalmology guidelines. We studied CFH (rs1329428, rs203687) and HTRA1 (rs11200638) SNPs thoroughly by logistic regression models (assuming different modes of inheritance) and machine learning-based methods (ML). HTRA1: rs11200638 is the most significant polymorphism associated with AMD in our studied population. In a multivariate regression model adjusted for clinically and statistically meaningful covariates, the A/G and A/A genotypes increased the odds of disease by a factor of 2.32 and 7.81, respectively (P < .05) suggesting a multiplicative effect of the polymorphic A allele. Furthermore, this observation remains statistically meaningful in the allelic, dominant, and recessive models, and ML algorithms. When stratifying by phenotype, this polymorphism was significantly associated with increased odds for geographic atrophy (GA) in a recessive mode of inheritance (12.4, p < .05). Conclusions: In sum, this work supports a strong association between HTRA1 genetic variants and AMD in Hispanics from Mexico, especially with GA. Moreover, ML was able to replicate the results of conventional biostatistics methods unbiasedly. © 2020 Taylor & Francis Group, LLC.

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Lack of Delta-Sarcoglycan (Sgcd) Results in Retinal Degeneration

2019 , Pérez Ortiz, Andric Christopher , Peralta-Ildefonso, Martha Janneth , Lira, Esmeralda , Ramírez-Sánchez, Israel , Brieva, Jorge , Moya-Albor, Ernesto , Clapp, Carmen , Luna-Angulo, Alexandra , Rendon, Álvaro , Adan-Castro, Elva , Ramírez-Hernández, Gabriela , Díaz-Lezama, Nundehui , Coral-Vázquez, Ramón , Estrada Mena, Francisco Javier

Age-related macular degeneration (AMD) is the leading cause of central vision loss and severe blindness among the elderly population. Recently, we reported on the association of the SGCD gene (encoding for δ-sarcoglycan) polymorphisms with AMD. However, the functional consequence of Sgcd alterations in retinal degeneration is not known. Herein, we characterized changes in the retina of the Sgcd knocked-out mouse (KO, Sgcd−/−). At baseline, we analyzed the retina structure of three-month-old wild-type (WT, Sgcd+/+) and Sgcd−/− mice by hematoxylin and eosin (H&E) staining, assessed the Sgcd-protein complex (α-, β-, γ-, and ε-sarcoglycan, and sarcospan) by immunofluorescence (IF) and Western blot (WB), and performed electroretinography. Compared to the WT, Sgcd−/− mice are five times more likely to have retinal ruptures. Additionally, all the retinal layers are significantly thinner, more so in the inner plexiform layer (IPL). In addition, the number of nuclei in the KO versus the WT is ever so slightly increased. WT mice express Sgcd-protein partners in specific retinal layers, and as expected, KO mice have decreased or no protein expression, with a significant increase in the α subunit. At three months of age, there were no significant differences in the scotopic electroretinographic responses, regarding both a- and b-waves. According to our data, Sgcd−/− has a phenotype that is compatible with retinal degeneration. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.

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Development of muscle atrophy and loss of function in a Gulf-War illness model: underlying mechanisms

2020 , Ramírez-Sánchez, Israel , Navarrete-Yañez, Viridiana , Garate-Carrillo, Alejandra , Loredo Mendoza, María Lilia , Lira, Esmeralda , Campeau, Anaamika , Estrada Mena, Francisco Javier , González, David , Carrillo-Terrazas, Marvic , Moreno-Ulloa, Aldo , Guillermo Ceballos , Villarreal, Francisco J.

Gulf War illness (GWI) afflicts military personnel who served during the Persian Gulf War and is notable for cognitive deficits, depression, muscle pain, weakness, intolerance to exercise, and fatigue. Suspect causal agents include the chemicals pyridostigmine (PB), permetrim (PM) and N,N-diethyl-m-toluamide (DEET) used as protectants against insects and nerve gases. No pre-clinical studies have explored the effects on skeletal muscle (SkM). Young male rats were provided PB, PM and DEET at equivalent human doses and physical restraint (to induce stress) for 3 weeks followed a 3-week recovery. GWI gastrocnemius weight was ~ 35% lower versus controls, which correlated with decreases in myofiber area, limb strength, and treadmill time/distance. In GWI rats, SkM fiber type relative abundance changed towards slow type I. Muscle wasting pathway proteins were upregulated while those that promote growth decreased as did mitochondrial endpoints and muscle ATP levels. Proteomic analysis of SkM also documented unique alterations in mitochondrial and metabolic pathways. Thus, exposure to GWI chemicals/stress adversely impacts key metabolic pathways leading to muscle atrophy and loss of function. These changes may account for GWI Veterans symptoms.