Dyslipidemia and Diabetic Retinopathy
Conditions: Diabetic Retinopathy, Dyslipidemia
Sponsor: University of Alabama at Birmingham

 
 
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Protocol Title Dyslipidemia and Diabetic Retinopathy 
 
 
 
Study Protocol & Statistical Analysis Plan 
 
NCT 03403283 
 
 
Date of Last Protocol Approval March 25-2024 
 
 
Maria Grant MD, Professor, Principal Investigator 
University of Alabama at Birmingham 
Birmingham, AL 35294 
 
 
 

 
 
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PROTOCOL SUMMARY 
1.1 SYNOPSIS  
Title: 
Dyslipidemia and Diabetic Retinopathy 
 
Study Description: 
Measurement of acid sphingomyelinase (ASM) activity in myeloid 
angiogenic cells 
Objectives: 
 
Determine if myeloid angiogenic cells isolated from diabetics with 
diabetic retinopathy have higher levels of ASM than age matched 
controls  
Endpoints: 
N/A 
Study Population: 
Diabetics and Age matched controls 
Phase: 
N/A 
Description of Study 
Intervention: 
N/A 
Study Duration: 
N/A 
Subject Duration: 
N/A 
 
 
 
 
 

 
 
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INTRODUCTION 
 
Study Rationale The purpose of this study is to determine if hematopoietic reparative cells are 
defective in individuals with diabetes. Diabetic 
retinopathy (DR) is an eye disease related to diabetes. It can cause blurred vision and 
possible bleeding from the blood vessels in the back of the eye (retina). Damage to the 
cells of the blood vessels from DR can initiate pathology that then may cause vision loss or 
blindness. Even with current treatments, the quality of life for people with DR is much 
reduced. 
 
Overall, this proposal will address the novel concept that the diabetes-induced decreases in 
DHA, and associated endothelial- speciﬁc increase in the central enzyme in sphingolipid 
metabolism ASM, aﬀects both retinal endothelial cells and bone marrow-derived EPCs. 
Understanding both mechanisms of damage and repair have the potential to lead to 
therapeutic strategies that will address the dyslipidemia observed in diabetic retinopathy and 
may ultimately lead to the prevention of diabetes-induced retinal damage. 
 
 
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STUDY DESIGN  
 
3.1 OVERALL DESIGN 
  
Peripheral blood (200 cc) is removed from diabetics with and without diabetic retinopathy. 
Blood sampling is done in the AM between 8-10 due to circadian variation in bone marrow 
cell release. 
3.2 END OF STUDY DEFINITION 
 
N/A 
 
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STUDY POPULATION 
 
4.1 INCLUSION CRITERIA 
 
1. Able to understand and sign an informed consent and HIPAA privacy 
document. 
2. 18 years of age or older at the time of informed consent 
3. Able and willing to follow protocol instructions. 
4. Presence of diabetic retinopathy by history, eye examination or by chart 
review. 
 
4.2 EXCLUSION CRITERIA 
 
1. Current use of tobacco products. 
2. Use of medication other than prescribed antidiabetic agents. 

 
 
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3. Other ocular disease  
4. Medical history of psychiatric illness. 
5. Illicit drug use and drug addictions. 
Insert text> 
 
4.3 SCREEN FAILURES 
N/A 
4.4 STRATEGIES FOR RECRUITMENT AND RETENTION 
 
Clinic subjects will be recruited.  
 
4.5 ADVERSE EVENTS AND SERIOUS ADVERSE EVENTS 
 There is minimal risk with a single blood draw and only infrequently is pain, bruising or 
infection at the site of the blood draw experienced. Occasionally a patient may feel faint 
during the blood draw and if this is the case, the patient will remain sitting for 
approximately 10 minutes until faint feeling dissipates.   
 
 
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STATISTICAL CONSIDERATIONS  
 
5.1 STATISTICAL HYPOTHESES AND ANALYSIS 
 
Diabetic individuals with diabetic retinopathy and age and gender matched controls were 
enrolled and CD34+ cells were isolated, and levels of ASM determined. All analyses were 
performed in GraphPad Prism v9.1 software. Prior to hypothesis testing, data were assessed for 
outliers, as indicated by the ROUT method, and outliers excluded from further analyses. Data 
underwent assessment for adherence to a normal (Gaussian) distribution using the Shapiro-
Wilks Normality test. Data which were found to be normally distributed were analyzed by an 
unpaired Student’s t-test (categorical predictor with 2 levels). For all statistical analyses, each 
input measure was indicative of a single, independent sample from one human subject. All data 
was analyzed at α=0.05.  
 
 
There have been 4 publications from this study.  
 
Cholesterol crystal formation is a unifying pathogenic mechanism in the development of diabetic 
retinopathy. Hammer SS, Dorweiler TF, McFarland D, Adu-Agyeiwaah Y, Mast N, El-Darzi N, 
Fortmann SD, Nooti S, Agrawal DK, Pikuleva IA, Abela GS, Grant MB, Busik JV.Diabetologia. 
2023 Sep;66(9):1705-1718. doi: 10.1007/s00125-023-05949-w. Epub 2023 Jun 14. PMID: 
37311879  
 
Intravitreal Administration of AAV2-SIRT1 Reverses Diabetic Retinopathy in a Mouse Model of 
Type 2 Diabetes. Adu-Agyeiwaah Y, Vieira CP, Asare-Bediako B, Li Calzi S, DuPont M, Floyd J, 
Boye S, Chiodo V, Busik JV, Grant MB. Transl Vis Sci Technol. 2023 Apr 3;12(4):20. doi: 
10.1167/tvst.12.4.20.PMID: 37070938. 

 
 
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Lipids, hyperreflective crystalline deposits and diabetic retinopathy: potential systemic and 
retinal-specific effect of lipid lowering therapies. Jenkins AJ, Grant MB, Busik JV.Diabetologia. 
2022 Apr;65(4):587-603. doi: 10.1007/s00125-022-05655-z. Epub 2022 Feb 11. PMID: 
35149880