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AA deficiency in various human diseases

Posted by UNDas on 08 Apr 2012 at 16:33 GMT

This study is interesting and reconfirms previous assertions that a decrease in the activities of delta-6- and delta-5-desaturases is present in subjects with obesity, hypertension, coronary heart disease, dyslipidemia, insulin resistance cancer and type 2 diabetes mellitus. It is possible that decrease in the activities of delta-6- and delta-5-desaturases may be the underlying common abnormality in all these diseases that are known to occur together. If this is true, perhaps, bypassing the block in delta-6- and delta-5- desaturases could form a novel method of preventing and managing these common conditions.

No competing interests declared.

RE: AA deficiency in various human diseases

GCBurdge replied to UNDas on 11 Apr 2012 at 11:58 GMT

This is an interesting perspective, but our data suggest an alternative view. We found that Fads2 expression was decreased in the adult offspring of dams fed a high fat diet which showed increased tendency towards vasoconstriction. However, Fads1 expression was increased. We interpreted these findings as suggesting an imbalance in the regulation of polyunsaturated fatty acid biosynthesis leading to increased production of arachidonic acid. Furthermore, inhibition of delta 6 or delta 5 desaturases reduced vasoconstriction in both rats and humans. This is in agreement with Kwak 2011 [ref 60] who showed that polymorphisms which decrease Fads expression and plasma arachidonic acid concentration appear to be cardioprotective. Therefore, bypassing a ‘block’ in arachidonic acid synthesis as you suggest may make the regulation of arterial tone worse. Based on the findings reported here, we suggest that arachidonic acid synthesis de novo is part of an early response to a1-adrenergic receptor stimulation and that arachidonic acid synthesised de novo in arterial smooth muscle may act as a metabolically channelled substrate for the synthesis of pro-constriction eicosanoids. Determining whether such metabolic channelling is involved may be important for resolving our different views.

No competing interests declared.