The Cures :) Live with Hopes

Today I am going to write about the current cures for Phenylketonuria :)

Dietary therapy is the standard current treatment. 

It involve a strict diet that with extremely low intake of Phe and supplementing Tyr which is the product of phenylalanine metabolism. Phenylalanine metabolism does not occurs in patients suffering from PKU.

Doctors recommend their patients to stick to this diet and PKU formula for life.

This is because PKU formula (devoid of/low in Phe) is essential to provide the body with protein substitution (acts as essential nutritional substitute), additional vitamins and minerals to support normal growth.

In earlier therapeutic protocols, treatment was only continued through the first few years of life, theoretically corresponding to the age at which brain myelination is complete. 

As developmental data accumulated, it became evident that treatment throughout childhood and adolescence was the best course for preserving intelligence. 

In more recent studies, it has been shown that brain MRI abnormalities and electrophysiologic testing abnormalities referable to the central nervous system are observed in adults who are on unrestricted Phe intake. 

Accordingly, it is reasonable to continue treatment into adulthood, and most centers recommend lifelong treatment. 

Strict adherence to the PKU diet is especially important for women during their reproductive years (before conception and throughout pregnancy) because of the risks to the fetus.

Taking supplements such as fish oil to replace the long chain fatty acids missing from a standard phenylalanine-free diet may help improve neurologic development, including fine motor coordination. Other specific supplements, such as iron or carnitine, may be needed.

Another possible addition to the PKU diet may be a supplement called large neutral amino acid therapy powder or tablets. This supplement may block some absorption of phenylalanine. However, this is an emerging treatment that hasn't yet been well-studied.

"Another theory suggests that abnormal brain myelination and deficiency of brain large neutral amino acids may play a role in impaired cognition."  

"Large neutral amino acids (LNAAs), including phenylalanine (Phe), compete for transport across the blood-brain barrier (BBB) via the L-type amino acid carrier. Accordingly, elevated plasma Phe impairs brain uptake of other LNAAs in patients with phenylketonuria (PKU). Direct effects of elevated brain Phe and depleted LNAAs are probably major causes for disturbed brain development and function in PKU. Competition for the carrier might conversely be put to use to lower Phe influx when the plasma concentrations of all other LNAAs are increased."

So, what kind of food should they avoid?

Food rich in Phe such as Milk, Cheese, Peas, Beer, Meat poultry (meat and eggs), Fish, Chocolate candies and also diet soda.
The artificial NutraSweet (Aspartame) also contain Phe, hence any food containing aspartame should also be avoided.
Adults and children with PKU should also have limited portions of low protein food such as desserts.

Medication

The drug called Sapropterin (Kuvan) is for use in combination with a PKU diet. It is an enzyme cofactor and oral form of tetrahydrobiopterin. Tetrahydrobiopterin (BH4) works with phenylalanine hydroxylase to metabolize Phe. It works by increasing the patient's tolerance to Phe as it reduces blood phenylalanine (Phe) levels in patients with hyperphenylalaninemia (HPA) due to tetrahydrobiopterin- (BH4-) responsive PKU.

However, it doesn't work for everyone with PKU.

The drug's efficacy and long-term safety is still under studies.

I will end off with this video.....the video talks abit what we've blogged about PKU. and she is teaching how to make a Fruit smoothie that is friendly to PKU patients! Hahaha :D so there's this recipe book available, called "Low-protein cookery for phenylketonuria" Mentioned in 4:03min inside the video... 
Ok, That's all for today!
CITATION

Gregg, Hanson, Lloyd-Puryear, Rasmussen, A. J. W. ,. M. A. ,. S. A. (2008). Maternal phenylketonuria. Retrieved 6 July, 2012 from http://pediatrics.aappublications.org/content/122/2/445.full

(2011) Phenylketonuria. Retrieved on 6 July, 2012, from Health Guide, by A.D.A.M. Copyright : http://health.nytimes.com/health/guides/disease/phenylketonuria/overview.html

Approved Drugs by FDA, Retrieved 6 July, 2012 from Medilexicon International: http://www.medilexicon.com/drugs/kuvan.php

(2011) Phenylketonuria – MayoClinic.com. Retrieved 7 July, 2012, from Mayo Clinic:http://www.mayoclinic.com/health/phenylketonuria/DS00514/dsection=treatments-and-drugs

Pietz, J (Pietz, J); Kreis, R (Kreis, R); Rupp, A (Rupp, A); Mayatepek, E (Mayatepek, E); Rating, D (Rating, D); Boesch, C (Boesch, C); Bremer, HJ (Bremer, HJ) (1999). Large neutral amino acids block phenylalanine transport into brain tissue in patients with phenylketonuria. Retrieved on 8 July, 2012 from http://cel.webofknowledge.com/InboundService.do?SID=X2i1Po8El41HhomCggI&product=CEL&UT=000079890400009&SrcApp=Highwire&Init=Yes&action=retrieve&Func=Frame&customersID=Highwire&SrcAuth=Highwire&IsProductCode=Yes&mode=FullRecord