Comparative study on the independent and combined effects of omega-3 and vitamin B12 on phospholipids and phospholipase A2 as phospholipid hydrolyzing enzymes in PPA-treated rats as a model for autistic traits.

BACKGROUND: Abnormal phospholipid metabolism is a major component of many neurodevelopmental disorders including autism. Oral administration of propionic acid (PPA) can produce behavioral abnormalities and biochemical features in rodents similar to those observed in autism and can thus be used as a model to understand impaired brain fatty acid metabolism in autism. METHODS: The present study was designed to understand alterations in phospholipid metabolism in the brain of a rodent model of autism and to explore omega-3 and vitamin B12 as remedies. Five groups of rats were selected: Group 1 was the control. Group 2 was the rodent model of autism treated with a neurotoxic dose of PPA. Group 3 was given vitamin B12 cobalamin (16.7 mg/kg/day) for 30 days after PPA treatment. Group 4 was given pharmaceutical grade Omega-3 (200 mg cholesterol free-DHA/kg body weight/day), a product of Madre lab, Germany, for 30 days after PPA treatment for 3 days. Group 5 was given a combined dose of ω-3 + Vitamin B12 for the same duration post-PPA treatment. Phospholipid levels and Phospholipase A2 were measured in the brain homogenates of all the groups. ELISA and western blotting were used to detect the cPLA2 protein level. RESULTS: A significant decrease in phospholipid levels and a significant increase in cPLA2 were found in brain tissue of PPA-treated rats; however, both ω-3 and vitamin B12 were efficient in ameliorating the neurotoxic effect of PPA. CONCLUSION: Both ω-3 and vitamin B12 may play a role in ameliorating impaired phospholipid metabolism in autism; however, proper clinical trials are needed.

Correlation between glycemic control and peripapillary retinal nerve fiber layer thickness in Saudi type II diabetics.

OBJECTIVE: To evaluate the effect of diabetes mellitus (DM), diabetic retinopathy, and degree of glycemic control (glycosylated hemoglobin [HbA1c]) on peripapillary retinal nerve fiber layer thickness (RNFLT) using optical coherence tomography. METHODS: The study included 126 eyes of healthy controls (n=32) and diabetics patients (n=31), whose ages ranged from 40 to 70 years. The diabetic group was divided into: Subgroup 1: with HbA1c <7% and Subgroup 2: with HbA1c ≥7%. All patients underwent full ophthalmic examination. HbA1c level was obtained with the A1cNow+ system and the peripapillary RNFLT was measured using 3D-OCT 2000 Topcon (360-degree circular scan with 3.4 mm diameter centered on optic disc). RESULTS: The obtained data demonstrates significant decrease in peripapillary RNFLT in superior and inferior quadrants of the right eye (p=0.000 and p=0.039, respectively), and in superior quadrant of the left eye (p=0.002) with impairment of glycemic control. Pearson's correlation test showed significant negative correlation of RNFLT with HbA1c in the superior quadrant in both eyes. CONCLUSION: Impairment of glycemic control affects the peripapillary RNFLT mainly in the superior quadrant. This thickness also tends to decrease with long-standing DM, use of DM medications, and development of diabetic retinopathy. The measurement of peripapillary RNFLT may become a useful method to monitor early retinal changes in diabetic patients.