NUTR 543
Advanced Nutritional Biochemistry

David L. Gee, PhD
Professor of Food Science & Nutrition
Department of Health, Human Performance, and Nutrition
Central Washington University

Summer 2007

 

Course Syllabus

NUTR 543 - ADVANCED NUTRITIONAL BIOCHEMISTRY
PROFESSOR DAVID L. GEE, PhD
SUMMER 2007

COURSE DESCRIPTION: Advanced study of the effects of micro- and macro- nutrients on human metabolism. Linkage of this information to the role of nutrition in long-term health and the prevention and treatment of disease.

COURSE OBJECTIVE: Apply current research information of nutrition and metabolism to the practice of dietetics.

Office: 109 HHPN Building
Phone Number: 963-2772
E-mail address:  geed@cwu.edu
Office Hours: Monday & Wednesday 2:30 - 3:30 or by appointment

Textbook:  Metabolism. 1st edition.  Carole J. Coffee.  1998. Fence Creek Publishing.
                This book is currently out of print.  The required readings are available at the Copy Shop.

                Metabolism at a Glance.  J.G. Salway., 3rd ed. , Blackwell Publishing, 2004 (optional)
                (same textbook that was used in NUTR 443- Nutrition II this past year)
 

Learner Outcomes

1.    The student will be able to describe the regulation of carbohydrate and lipid metabolism as they are affected by different physiological states.

2.    The student will be able to describe the process of protein catabolism with an emphasis on amino acid nitrogen disposal.

3.    The student will be able to apply this knowledge by presenting a professional presentation of a clinical case study.
 

Grading Policy
 
 
 

Exam 1: July 2 covers Carbohydrate Metabolism (Chapters 8, 9, 11, 12, 13, 14)	100 points
Exam 2:  July 16 covers Fat and Protein Metabolism (Chapters 19, 20, 21, 23)	100 points
Exam 3: July 26 covers Protein Metabolism and case studies (chapter 25)	100 points
Case Study (50% peer evaluation, 50% instructor evaluation - includes quality of questions)	100 points
Total	400 points

 
 
 
 

Case Study Presentations
Each student has been assigned to present (as a team) a case study.  Prepare to give a 30 minute presentation on your case study.  Your presentation should include an overview of the case, a review of the metabolic aspects of the case, and the nutritional implications of the case.  Each person on the team will present an equal portion of the case.  Evaluation will be on the entire presentation with equal points being given to both members of the team.  One half of the grade will be based on evaluations by your peers and one half by your instructor.  The evaluation will be based on the following scoring system:
 
 

Clarity of presentation	Were the concepts presented to you in a clear and concise manner?	15 points
Ability to answer questions	Did the presenters display adequate knowledge to answer questions related to the case study?	10 points
Use of visual aids	Did the presenters use visual aids (whiteboard, overheads, Powerpoint slides) effectively to assist in the transmission of knowledge?	10 points
Overall quality of presentation		15 points
TOTAL		50 points

 

Format of Case Study Presentation
I.     Overview of Case Study
II.    Background Information
        A.  Reviews the biochemical and metabolic information that is relevant to this particular case study
III.   Case Study Presentation
        A.  Application of biochemical/metabolic information to case study
        B.  Nutritional/dietary factors relevant to case study
        C.  Nutritional care/treatment and rationale

Required Written Material
1.     Learning Objectives
        a.  What essential concepts should the learner gain from listening to your presentation?
        b.  Learning Objectives should be presented to the class as a handout and/or overhead projection
2.     Multiple choice questions
        a.  Presenters shall prepare 6 multiple choice questions that aid in determining whether learning objectives were met.
        b.  Questions should be challenging and require that the learner was able to answer the question because of your
             case presentation
        c.  Please submit your questions as a Word document attached to an email to geed@cwu.edu
3.     Acknowledgment of  Student Judicial Code regarding proscribed academic conduct.
        a.  Student shall sign the following statement:  I acknowledge the Student Judicial Code (WAC 106-120) which
               recognizes the importance of academic integrity and certify that these submitted questions have not
               been shared with any other student in the class other than members of  my presenting team.
4.     These written materials are to be turned in the day of your presentation.

Case Study Topics
 
Case Study - Pyruvate Dehydrogenase Deficiency
Case Study - Von Gierke's Disease
Case Study - Hypoglycemia  
Case Study - Fructose Intolerance
Case Study - Secondary Prevention of Coronary Heart Disease 
Case Study - Alcoholic hepatitis 
Case Study - Protein Catabolism and Trauma 
Case Study - Phenyketonuria
Case Study - Homocystinuria
 
 
 

Course Schedule

Week of June 18-21 (MTWTh)
Regulation of Metabolism (Chapter 8)   (Powerpoint slides)
Overview of Carbohydrate Metabolism (Chapter 9)  (Powerpoint slides)
Glycolysis (Chapter 11)  (Powerpoint slides)

Week of June 25-28 (MTWTh)
Glycogen Metabolism (Chapter 12) (Powerpoint slides)
Gluconeogenesis (Chapter 13, MAAG: Chapter 23) (Powerpoint slides)
Pentose Phosphate Pathway (Chapter 14, MAAG: Chapter 12) (Powerpoint slides)

Week of July 2-5 (MTTh)
Exam 1 (Carbohydrate Metabolism) (Monday, July 2)
Lipid Transport (Chapter 19)

Week of July 9-12 (MTWTh)
Fatty Acid Metabolism (Chapter 20)
Cholesterol and Sterol Metabolism (Chapter 21)
Pathways of Lipid Metabolism (Chapter 23)

Week of July 16-19 (MTThF)
Exam 2 (Lipid Metabolism) (Monday July 16)
Amino Acid Catabolism (Chapter 25) (Powerpoint slides)
Protein metabolism
Case Study Presentations

Week of July 23-26 (MTWTh)
Case Study Presentations
Exam 3 (Protein Metabolism and Case Studies) (Thursday, July 26)

Overview of Amino Acid Catabolism
David L. Gee, PhD
Central Washington University
FCSN 543 - Advanced Nutritional Biochemistry

AA catabolism: Feeding Intestine
Uses glutamine and asparagine as major source of energy
Releases into portal blood
other dietary amino acids
ammonia, carbon dioxide, alanine

AA catabolism: Feeding Liver
takes up most of the dietary amino acids
makes hepatic and plasma proteins
removes amino group and incorporates it into urea (major site of urea formation)
carbon skeleton for energy, fat synthesis
does not catabolize BCAA
releases AA enriched in BCAA

AA catabolism: Feeding Skeletal Muscle
Uses plasma AA for protein synthesis
Major site of BCAA catabolism
sends amino groups out mainly as alanine and glutamine

AA catabolism: Feeding Kidney
Removes much of the glutamine from muscle
deaminates and forms ammonia (excreted into urine as ammonium ion)
carbon skeleton used for energy or converted to glucose
Excretes urea made in liver

AA catabolism: Fasting Muscle
Major “storage” of amino acids
can use as source of energy
releases all amino acids into plasma, enriched with alanine and glutamine

AA catabolism: Fasting Kidneys
Removes glutamine
produces and excretes ammonium ion
produces glucose from carbon skeleton
excretes urea made in liver

AA catabolism: Fasting Liver
Takes up most amino acids
site of gluconeogenesis
releases glucose into blood
site of urea synthesis
from AA-nitrogen and ammonia
releases urea into blood

Urea Synthesis / Urea Cycle
Overall reaction
NH4 + CO2 + 3ATP + aspartate -> urea + fumerate + 2ADP + AMP + Pi
Details of urea cycle
genetic deficiency 1 in 25,000 live births
deficiency found for each enzyme
neonatal hyperammonemia (mental retardation, convulsions, coma, death)
Integrated with TCA cycle

Flow of Nitrogen to Urea
transamination of AA-N to glutamate
transamination of glutamate to aspartate
deamination of glutamate to ammonia
incorporate N from aspartate and ammonia into urea

Regulation of Urea Cycle
Short term regulation
CPS-1 chief regulatory enzyme
hi levels of glutamate (reflects increased protein degradation) activates CPS-1 (via N-Acetyl Glutamate)
Long term regulation
enzymes induced with high protein diet or starvation
enzymes repressed with low protein diet

Clinical Case Study
Male infant, 2.9 kg at birth, healthy
Day 3 - seizures
Mother with history of aversion to meat
vomiting and lethargy
mild alkalosis (pH=7.5, normal 7.35-7.45)
plasma NH4+ = 240 uM (25-40 normal)

Clinical Case Study
Plasma AA
gln = 2400 uM (350-650)
ala = 750 uM (8-25)
arg = 5 uM (30-125)
cit = undetectable
Urinary orotic acid = 285 ug/mg creatinine (0.3-10)

Clinical Case Study
Treatment
Oral therapy essential amino acids
arginine
sodium benzoate
@7 days clinically well
normal NH4+

Resolution of Clinical Case
Diagnosis of neonatal hyperammonemia
symptoms
blood ammonium concentration
Defect in urea cycle
elevated glutamine and alanine
low or absent arginine and citrulline

Resolution of Clinical Case
Genetic deficiency of ornithine transcarbamoylase
urinary orotic acid
CP spills into cytosol where enters pyrimidine biosynthetic pathway, orotic acid an intermediate in the pathway

Resolution of Clinical Case: Treatment
Essential Amino Acids
Arginine
w/o urea cycle, becomes essential
Benzoic acid
conjugates with glycine and excreted in urine as hippuric acid
glycine in equilibrium with ammonia
removal results in reducing ammonia levels

Resolution of Clinical Case: Genetics
Gene for OTC found on X-chromosome
Women are carriers
usually asymptomatic
may experience migraines, vomiting, lethargy when eating high protein meals (meat)

Syndrome X.

At his current office visit, Thomas Appleman’s case was reviewed by his physician.  Mr. Applemna has several of the major risk factors for coronary heart disease (CHD).  These include a sedentary lifestyle, marked obesity, hypertension, hyperlipidemia, and early non-insulin dependent diabetes mellitus.  Unfortunately, he has not followed his doctor’s advice with regard to a diabetic diet designed to effect a significant weight loss nor has he followed an aerobic exercise program.  As a consequence, his weight has gone from 270  to 281 lb.  After a 14 hour fast, his serum glucose is now 214 mg/dL and his serum total cholesterol level is 314 mg/dL.  His serum triacylglycerol level is 295 and his serum HDL cholesterol level is 24 mg/dL.  His calculated serum LDL-cholesterol is 231 mg/dL
 
 
 
 
 

Secondary Prevention of Coronary Heart Disease

William Hartman was carefully followed by his physician after he survived his heart attack.   Prior to discharge from the hospital, after a 14-hour fast, his serum triacylglycerol level was 158 mg/dL. And his HDL-cholesterol was slightly low at 32 mg/dL.  His serum total cholesterol was elevated at 420 mg/dL and his calculated LDL-C level was 356 mg/dL.  Both of Mr. Hartman’s younger brothers had “very high” serum cholesterol levels and both had suffered heart attacks in their mid-forties.   With this information, a tentative diagnosis of familial hypercholesterolemia, type IIA was made and the patient was started on a Therapeutic Lifestyle Change Diet.

Because Mr. Hartman continued to experience intermittent chest pain is site of good control of hy hypertension and a 20 pound weight loss, his physician decided that two-drug regimen to lower his blood LDL cholesterol  must be added to the dietary changes already made.  Consequently,  treatment with cholestyramine and pravastatin was initiated.
 
 
 
 

Hypoglycemia

Mrs. J is a 30 YOBF.  Mrs. J has been feeling dizzy and weak.  Her husband was afraid she had high blood ressure since it runs in her family.  Her father died with a stroke and she has a sister with renal failure because of high blood pressure.  She went to her doctor who examined her and found her blood pressure to be normal.  However, her blood sugar was very low, 48 mg/dl.  To Mrs. J’s knowledge, there is no family history of diabetes or hypoglycemia.  The doctor’s examination revealed the following:  Mrs. J has not been eating as usual because of their poor financial state.  She has been eating a lot of high carbohydrate foods that are easy to fix and inexpensive.  She has also been eating a lot of bread with her meals because it is filling.  About two hours after eating she becomes dizzy, weak, anxious, sweats profusely, and just ‘does not feel well’.  If she lies down, the symptoms usually pass.  The MD thought the problem was reactive functional hypoglycemia based on a high carbohydrate intake accompanied by hyperepinephrinemia  secondary to nervousness. To be sure, he ordered a 5 hour GTT.  Mrs J felt sick after drinking the glucose solution and began throwing up after about 3 hours  and the test had to be stopped.  The results at that time were: FBS=70mg/dl, 30min=130mg/dl, 1h=160mg/dl, 2h=90mg/dl, 3h=54mg/dl.  The physician felt that this was sufficient to diagnose Mrs. J as having reactive functional hypoglycemia secondary to malnutrition and nervousness.  He referred her to the dietitian for nutrition counseling.
 
 
 
 

Fructose Intolerance
Nona M is a 7 month old bably girl.  Her mother had a healthy, full term pregnancy, and Nona’s birth weight was normal.  She did not respond well to breast feeding and was changed entirely to a formula based on cow’s milk at 4 weeks.  Between 7 and 12 weeks of age, she was admitted to the hospital twice with a history of screaming after feeding, but was discharged after observation without a specific diagnosis.  Elimination of cow’s milk from her diet did not relieve her symptoms.  Nona’s mother reported that the screaming bouts were worse after Nona drank juice and that Nona frequently had gas and a distended abdomen.  At 7 months she was still thriving (weight above the 97th percentile) with no abnormal findings on physical examination.  The association of Nona’s symptoms with her ingestion of fruit juices suggests that she might have a problem with fructose or sucrose malabsorption resulting from a deficiency of sucrase activity or an inability to absorb fructose.  Her ability to thrive and her adequate weight gain suggest that any deficiencies of the sucrase-isomaltase complex must be partial and do not result in a functionally important reduction in maltase activity.  Therefore a hydrogen breath test after Nona ingested test meals containing fructose, lactose, and sucrose was performed.  The large amount of hydrogen produced with fructose suggested that Nona’s problem was one of a deficiency in fructose transport into the intestinal absorptive sells.  To confirm the diagnosis, a jejunal biosy was taken; lactase, sucrase, maltase and trehalase activities were normal.  The tissue was also tested for the enzymes of fructose metabolism; there were in the normal range as well.  The physician made a diagnosis of fructose intolerance and referred her to the dietitian for nutrition counseling.
 
 
 
 
 

Von Gierke’s Disease
The patient was a 12 year-old girl who had a grossly enlarged abdomen.  She had a history of frequent episodes of weakness, sweating, and pallor that were eliminated by eating.  Her development had been somewhat slow; she sat at 1 yr of age, walked unassisted at 2 yr., and was doing poorly in school.  Physical examination revealed blood pressure=110/58, temperature=38 deg C, weight=22.4kg, height=128cm.  Slight venous distention was present over the prominent abdomen.  The liver was enlarged, firm, and smooth and was descended into the pelvis.  The remainder of the physical examination was within normal limits except for ‘poor musculature’.  The following are laboratory findings for a fasting blood sample: hypoglycemia, elevated levels of lactate, pyruvate, free fatty acids, triglycerides, and ketoacidosis.  Total blood CO2 were below normal.  A liver biopsy specimen was obtained.  The liver was huge, buff-colored, and firm but not cirrhotic.  Histologically the hepatic cells were bulging and dilated.  Portal areas were compressed and shrunken.  No inflammatory reaction was present.  Stain for carbohydrate revealed large amounts of positive material in the parenchymal cells that as removed by digestion with salivary amylase.  Glycogen content was elevated as was lipid content.  Hepatic glycogen structure was normal.  Enzyme assays were conducted on the biopsy tissue and the following were found:  very low glucose-6-phosphatase and normal G-6-P dehydrogenase, phosphoglucomutase, phosphorylase, and fructose-1,6-bisphosphatase activities.  The physician made a diagnosis of Von Gierke’s disease and referred her to the dietitian for nutrition counseling.
 
 
 
 
 
 

Pyruvate Dehydrogenase Deficiency
A full-term male infant failed to gain weight, had episodes of vomiting and showed metabolic acidosis in the neonatal period.  A physical examination at 8 mo showed failure to thrive, hypotonia, small muscle mass, severe head lag, and a persisten acidosis, pH 7-7.2.  Blood lactate, pyruvate, and alanine were greatly elevated.  Since these symptoms suggested a genetic defect in pyruvate metabolism, treatment with thiamine, biotin, bicarbonate, protein restriction, and a ketogenic diet were all tried, but none of the treatments alleviated the lactic acidosis.  Enzyme activity of the PDH complex, alpha-ketoglutarate dehydrogenase complex, and dihydrolipoyl dehydrogenase from sonicated skin fibroblasts grown in culture were all low when compared with enzymes from normal fibroblasts.  Dihydrolipoyl dehydrogenase was especially low.  After informed consent, oral lipoic acid greatly improved the lactic and pyruvic academia.  The patient was doing well 2 years later.
 
 
 
 
 
 

Alcoholic Hepatitis
Jean T, a 46 yo commercial artist, recently lost her job because of absenteeism.  Her husband of 24 years had left her 10 months earlier.  She complains of loss of appetitie, fatigue, muscle weakness, and emotional depression.  She has had occasional pain in the area of her liver.  On physical examination she appears somewhat disheveled and pale.  The physician notes tenderness to light percussion over her liver and detects a small amount of ascites and an enlarged liver.  There is a suggestion of mild jaundice.  After noting a hint of alcohol on her breath, the physician questioned her about possible alcohol abuse.  The patient admits that for the last 5 or 6 years, she began drinking gin on a daily basis in quantities of about 50-70g of ethanol while eating relatively poorly.  Because of the possibility of mild alcoholic hepatitis and perhaps chronic alcoholic cirrhosis, the physician ordered liver function studies.  These revealed elevated alanine transaminase activity, aspartate transaminase activity, and hyperbilirubinemia.  Tests for viral hepatitis were negative.  Her blood hemoglobin and hematocrit levels were slightly below the normal range as were her serum levels of folate, vitamin B-12, and iron.  Her serum ethanol levels on the initial office visit was 245 mg/dL, a level considered indicative of inebriation.
 
 
 
 
 
 

Homocystinuria
A 6-yo girl was brought to the hospital with vision problems.  She was found to have a downward dislocation of the left lens.  Her mother indicated that the girl’s birth was normal but that she lagged in development.  She was unable to crawl until 1 yr old and did not walk until 2 yr.  Speaking was also delayed.  She had long, thin bones; on roentgenographic examination the lower femur showed signs of osteoporosis.  An older brother had similar symptoms but had been diagnosed as having Marfan’s syndrome.  A simple cyanide-nitroprusside test of the patient’s urine was positive, suggesting homocystinuria, not Marfan’s syndrome.  This was confirmed by amino acid analysis of the plasma, which revealed homocystine, and abnormally high methionine levels, and other sulfur-containing compounds that were derivatives of homocysteine.  A liver biopsy found a deficiency of the enzyme cystathione-beta synthase.  The patient was treated with a low-methionine diet supplemented with folic acid and pyridoxine
 
 
 
 
 
 
 

Phenylketonuria
The patient was a 2 week old female who responded positively to a test for phenylketonemia administered on discharge from the hospital following her birth.  She was called back for further testing.  Serum phenylalanine concentration was found to be elevated.  Serum tyrosine levels were below normal.   Had a liver biopsy been performed and a defective phenylalanie hydroxylase (type I) would have been found.  The enzyme dihydrobiopterine reductase was found to be normal.   The urine was positive for phenolic acids, ferric chloride, and ketones.  A diagnosis of classic phenylketonuria  (PKU) was made and the child was maintained on a diet low in phenylalanine.
 

Protein Catabolism and Trauma
Jerone, a 36 yo African American male (dry wt=108.9kg, ht=64", BMI=41) was admitted to the trauma unit at a Level One Trauma Center with multiple trauma due to a small abdominal laceration obtained from falling on a shovel while playing with his nieces in their yard. Nutrition support was challenging during the first 2 weeks of hospitalization. After failing to advance to goal on Traumacal, a TF formula, TPN was initiated during week 3 as follows: TPN=D70(500ml), 15%AA (750ml), 20%IL (350ml) to provide 2340kcals and 112.5g PRO. His needs were calculated as 2323-2681kcals (BEEx1.3-1.5) and 126g PRO (1.5g/kg) based on an adjusted weight of 84kg due to obesity. The RD noted that at that time Jerone was receiving a Propofol gtt >25ml/hr, therefore she held his TPN lipids to avoid hyperlipidemia. By week 4 Jerone was not improving and his abdomen remained open with several fistulas forming. TPN formulation was altered=D70 (450ml), 15%AA (850ml), 20%IL (250ml) to provide 2081kcals and 128g PRO. The Resident asked for additional PRO be administered during week 6 - the RD added a glutamine packet TID per Jerone's OG tube for a total of 2261kcals and 158g PRO with the TPN solution.

Two months following admit, Jerone continues to be in critical condition with an open abdomen and fistulas everywhere. The team says that he will continue to be TPN dependent for several months to come. The RD remains concerned that Jerone is losing a lot of LBM with catabolism and bedrest. His temples are sunken after diuresis despite being provided with adequate nutrition support based on metabolic cart study results.