High-Density Lipoprotein-Associated Cholesterol Abnormalities in a Clinical Outcomes Study of Dysferlin-Deficient...

Area of Science:

• Biochemistry
• Genetics
• Neurology

Background:

• Limb-girdle muscular dystrophy type R2 (LGMDR2) is an autosomal recessive muscular dystrophy caused by DYSF gene variants.
• LGMDR2 leads to progressive muscle weakness, impacting ambulation but typically not causing fatal cardiorespiratory issues.
• The mechanisms of muscle fiber death in LGMDR2 are unclear, but links to cholesterol imbalance and lipoprotein abnormalities are emerging.

Purpose of the Study:

• To investigate the prevalence of dyslipidemia in a large cohort of LGMDR2 patients.
• To explore potential correlations between lipid abnormalities and disease severity or ambulatory function.

Main Methods:

• Collected cross-sectional data on circulating lipids (total cholesterol, HDL-C, non-HDL-C) and muscle enzymes (CK, transaminases, bilirubin) from 188 LGMDR2 patients.
• Assessed ambulatory function in the Jain Clinical Outcomes Study of Dysferlinopathy cohort.
• Analyzed lipid profiles and their relationship with clinical parameters.

Main Results:

• A high percentage of LGMDR2 patients, particularly males, exhibited abnormal cholesterol levels (CHOL, HDL-C, non-HDL-C).
• Nearly 70% of the cohort had at least one abnormal cholesterol value, and 89% of males had suboptimal CHOL/HDL-C ratios.
• No significant correlation was found between lipid abnormalities and the loss of ambulation; lower transaminases suggested reduced muscle mass.

Conclusions:

• Dyslipidemia is a significant comorbidity in LGMDR2 patients.
• The findings support the need for further investigation into the role of cholesterol abnormalities in LGMDR2 pathogenesis.
• This study provides crucial natural history data for LGMDR2.