Purpose To detect whether a 3243 point mutation existed in age-related macular degeneration (AMD). MethodsTwenty-six cases of wet form AMD patients, ten cases of dry form AMD patients were selected,and compared with twenty nomal controls. After collecting anti-coagulated blood samples, total cellular DNA were extracted and purified. Using polymerase chain reaction and restriction fragment long polymorphism techniques, the mtDNA Ararr;G point mutation at position 3243 were detected. Results After cleaveded by restriction endonuclease Apa I, a 294 bp fragment remained only in all detected DNA samples including twenty-six wet form AMD, and ten dry form AMD. No any other fragment appeared. The result showed that there was no Ararr;G mutation at position 3243 found in AMD. Conclusion It is suggested that mtDNA 3243 point mutation due to maternal inheritance might be not concerned with both wet form AMD and dry form AMD. (Chin J Ocul Fundus Dis,2000,16:231-232)
MiRNAs are stable small RNAs that are expressed abundantly in animals and plants. They can bind to the 3'-untranslated region of the target mRNA, and regulate its expression at the post-transcriptional level. The miRNAs’ abnormal expression and its following abnormal biological regulation are closely related to the occurrence and development of age-related macular degeneration (AMD), including inflammatory response, oxidative stress injury, phagocytosis dysfunction and abnormal angiogenesis. Since the dysregulation of miR-155, miR-125b and miR-34a seems to play a more important role in AMD, these microRNAs may be expected to become the new biomarkers and therapeutic targets for AMD.
Macular pigment (MP) is composed of lutein, zeaxanthin, and meso-zeaxanthin, which accumulate mainly at the macula. MP has antioxidant function and can filtering blue wave. Measurement of MP is about its optical density, that is, macular pigment optical density (MPOD). This review summarizes the function and clinical use of MP and MPOD. Researches has show that MPOD is related to some ocular disease such as age-related macular degeneration, macular telangiectasia type 2, diabetic retinopathy, Stargardt disease et al. MPOD can be used in the judgment of clinical diagnosis, treatment effect. The specific mechanism of MP metabolism in the retina and in the pathogenesis of the disease, genotype specific nutritional therapy of xanthophyll, the establishment of a database combined with artificial intelligence and the rapid and convenient MP determination are all issues of great contention that need to be resolved.
Dysregulation and activation of immune processes are important in age-related macular degeneration (AMD) pathogenesis. The single nucleotide polymorphism of complement factor H is widely recognized as a risk factor to AMD. Over-activation of nod-like receptor3 and polymorphism of Toll-Like Receptor 3 also associated with AMD. Except for innate immune processes, adaptive immunity also play a critical role in AMD, a growing body of evidence supports that auto-antibodies and T cells are related with AMD. Additionally A2E and lipid oxidation byproducts might also have a role in AMD pathogenesis.
Objective To investigate the serum levels of vitamin B12 and folic acid (FA) of exudative agerelated macular degeneration (AMD).Methods A total of 84 patients with exudative AMD（AMD group）and 78 patients with non-exudative AMD （control group） diagnosed at Xijing Hospital between June 2008 and September 2009 were assessed in this study. Serum vitamin B12 and FA levels were measured by chemiluminescence immunoassay. The statistical information of epidemiology and risk factors exposure histories were collected and compared.Results AMD group had significantly lower serum vitamin B12 levels ［（247.51plusmn;93.92）ng/ml］ compared with the control group ［（312.52plusmn;143.08） ng/ml］，the difference was statistical significance (t=5.013, P＜0.001). Serum FA levels in AMD group ［（5.64plusmn;3.72）ng/ml］ were slightly lower than the control group ［（10.14plusmn;4.48） ng/ml］, the difference was not statistical significance (t=0.780, P=0.437).Conclusion People with lower serum vitamin B12have higher risk of exudative AMD. Low levels of serum vitamin B12 may relate with the occurrence of exudative AMD.