Effects of the Tibetan herbal preparation PADMA 28 on blood lipids and lipid oxidisability in subjects with mild hypercholesterolaemia.
BACKGROUND
Previous studies showed an anti-atherosclerotic effect of PADMA 28, an herbal formula based on Tibetan medicine. As the mechanisms of action are not fully understood, we investigated whether PADMA 28 may lower blood lipids and lipid oxidisability, and affect early endothelial dysfunction.


METHODS
Sixty otherwise healthy subjects with total cholesterol > or = 5.2 mmol/l and < 8.0 mmol/l were randomly assigned to placebo or PADMA 28, 3 x 2 capsules daily, for 4 weeks (double-blind). Blood lipids (total, LDL-, and HDL-cholesterol, triglycerides, Apo-lipoprotein A1 and B) and ex vivo lipid oxidisability were measured before and after treatment. In a subset of 24 subjects, endothelial function was assessed using venous occlusion plethysmography with intraarterial infusion of acetylcholine. Isolated LDL and plasma both untreated and pre-treated with PADMA 28 extract were oxidised by the radical generator AAPH. Conjugated diene formation was measured at 245 nm.


RESULTS
Blood lipids did not change during the study in both groups. In contrast to previous reports in mild hypercholesterolaemia, no endothelial dysfunction was seen and, consequently, was not influenced by therapy. Ex vivo blood lipid oxidisability was significantly reduced with PADMA 28 (area undercurve: 5.29 +/- 1.62 to 4.99 +/- 1.46, p = 0.01), and remained unchanged in the placebo group (5.33 +/- 1.88 to 5.18 +/- 1.78, p > 0. 1). This effect persisted one week after cessation of medication. In vitro experiments confirmed the prevention of lipid peroxidation in the presence of PADMA 28 extracts. Persistent protection was also seen for LDL isolated from PADMA 28-pretreated blood after being subjected to rigorous purification.


CONCLUSIONS
This study suggests that the inhibition of blood lipid oxidisability by PADMA 28 may play a role in its anti-atherosclerotic effect.
Brunner-La Rocca
H P
HP
Interdisciplinary Clinical Research Unit, University Hospital, Basel, Switzerland. brunnerh@uhbs.ch
Schindler
R
R
Schlumpf
M
M
Saller
R
R
Suter
M
M
D000328:Adult; D001161:Arteriosclerosis / Q000097:blood / Q000188:drug therapy; D002214:Capsules; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000188:drug therapy*; D066298:In Vitro Techniques; D015227:Lipid Peroxidation / Q000187:drug effects*; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D008517:Phytotherapy; D010936:Plant Extracts / Q000627:therapeutic use*
D002214:Capsules; D008055:Lipids; D010936:Plant Extracts; C066069:Padma 28