Published Paper1- Caffeine and Diabetes, are They Related? :o

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Lane, James D. “Caffeine, Glucose Metabolism, and Type 2 Diabetes.” JOURNAL OF CAFFEINE RESEARCH 1, no. 10.1089 (2011): 23-28, http://online.liebertpub.com/doi/pdfplus/10.1089/jcr.2010.0007 (accessed 13th April, 2013).

Hi everyone! The above is the reference to my first published paper on Caffeine, Glucose Metabolism and Type 2 Diabetes. I chose the topic of caffeine because I myself am a huge caffeine user, especially when it comes from French Vanilla coffee or Monster Energy Drink.

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I also have it in my genetics to become diabetic due to all of my grandparents and some of my aunts and uncles having Type 2 Diabetes and I am curious to see if there is a link between the two. So the following is a summary of this journal article, which answered my question.

Type 2 Diabetes Mellitus is when insulin receptors in muscle, liver and fat cells become resistant to insulin, such that increasing the secretion of insulin by the pancreas does not overcome this resistance. Since insulin is responsible for the absorption of glucose into cells, the glucose levels in the blood increases and this is called hyperglycemia and results in Type 2 diabetes.  It is believed that caffeine decreases the risk of diabetes. However, this review proves the opposite, where caffeine increases the risk of insulin resistance.  

A study was carried out using both healthy and Type 2 diabetes individuals. Firstly, their glucose and insulin levels were measured under fasting conditions and then repeatedly after several hours of a standard dose of glucose administration. The healthy non-diabetic individuals showed an increase in blood glucose levels followed by an increase in insulin levels. After an hour or two, these levels dropped back down to the fasting values. When caffeine was ingested, insulin levels increased however there was no decrease in glucose levels. This proved that in healthy, non-diabetic individuals, caffeine produces an acute reduction in insulin sensitivity/ increased insulin resistance. Individuals who have Type 2 diabetes already have small insulin reserves and hence a small increase in carbohydrate can cause hyperglycemia. However, the same effect occurred when caffeine was ingested.

Although the exact mechanism on how caffeine affects glucose tolerance is not known, there are two hypotheses as to what may occur. Caffeine is an inhibitor to adenosine receptors (adenosine promotes sleep,) so the first hypothesis assumes that adenosine has some effect on insulin-mediated glucose transport and insulin responsiveness. The second hypothesis assumes that caffeine impairs glucose metabolism by the release of stress hormones (eg. Epinephrine and cortisol), which stimulate production of glucose in the liver and inhibiting insulin action.

Although these studies and experiments have proved that caffeine does indeed increase the risk of Type 2 diabetes, no body of evidence is without its weaknesses and limitations. Therefore, the results from the epidemiological studies that show the opposite must still be taken into account.

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The End.

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Hey dudes and dudettes! We have come to the end of a great semester of blogging and I hope you all learnt a lot from my blog and from our classes at school. Sadly, we must now part from our awesome BIOL1362 Biochemistry course, but we won’t forget all that we’ve learned, the adventures and memories we had in our labs and our wonderful and awesome biochemistry lecturer, Mr. Matthew.

Onward we go into our final exams, and I hope you are all prepared. I wish everyone luck (although we should not need it :p ) and I shall see you all on the other side. Fear not, we got this! B)

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Goodbye for now, from celestembiochem (a.k.a. Celeste R. Mohan).

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Published Paper2- Benefits of Yogurt

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 Yogurt comes in many brands and flavors and can serve as a snack or as breakfast, but one thing is certain: it is very healthy for us. The following summary of mine came from the article for my second published paper review (as referenced below). It entails all the nutritional and health benefits of yogurt, some you probably never heard of. I chose this topic because I am just as obsessed with yogurt as I am with caffeine.  Happy reading!

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Mckinley, Michelle C. “The nutrition and health benefits of yoghurt.” International Journal of Dairy Technology 58, no. 1 (2005): 1-12, http://www.aseanfood.info/Articles/11024970.pdf (accessed 13th April, 2013).

Yogurt is a fermented milk product that contains many nutrients needed by the human body, especially the large amounts of calcium. It is produced by the lactic acid fermentation of milk by addition of a starter culture containing Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. Studies show that by using different microorganisms for fermentation, the variety of textures, flavors, consistencies and health attributes that we see today can be made. Yogurt has nutritional similarities to milk, such as high levels of proteins, vitamins (A, B12, D) and minerals (Calcium, Potassium, Phosphorus, Magnesium and Zinc) . As a diary product, yogurt provides important nutrients in significant amounts in relation to their energy and fat content, making them a nutrient-dense food.

Yogurt contains the enzyme β-galactosidase which hydrolyses lactose and therefore improves the conditions known as lactose intolerance.  Experiments were also carried out to determine if milk products, such as yogurt, increased the possibility of weight gain. The results of these experiments proved that the calcium in these milk products helps reduce weight and fat in the trunk region of the human body.

It has also been proven that the non-pathogenic bacteria used in yogurt, when ingested, survive the harsh conditions of the digestive tract and colonizes certain areas of the gut and provide the body with resistance to disease and promotes normal intestinal function. These probiotics also help in preventing and treating diarrhea that was caused by pathogenic bacteria, viruses and antibiotics. Studies have shown that the consumption of yogurt increases cytokine production, phagocytic activity, antibody production, T-cell function and natural killer cell activity. This just shows that the probiotics in yogurt help increase immunity in the body.

Inflammatory Bowel Disease (IBD) and Irritable Bowel Syndrome (IBS) are both characterized by intestinal inflammation and abdominal pain, constipation and diarrhea. Probiotics found in yogurt are thought to interrupt these immuno-inflammatory responses and calm the inflammation of the intestinal tract, however further research needs to be done to confirm this theory.

Because of its health and nutritional benefits, there may be and increased production in the yogurt industry in the years to come.

The Return of Enzymes

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So I’m back again with another quiz, this time based on enzymes. However this quiz is a little different from the ordinary multiple choice quizzes you usually see. Don’t panic! Its fairly simple and I’m sure you will all get the hang of the answer key pretty quickly. Again, it’s just for you to review the topic, so have fun! 😀

For questions 1-10, choose the correct multiple answer using ONE of the keys A, B, C, D or E as follows:

A. 1, 2 and 3 are correct

B. 1 and 3 are correct

C. 2 and 4 are correct

D. Only 4 is correct

E. All are correct

1)      What is an enzyme?

  1. A biological catalyst
  2. Speeds up chemical reaction
  3. Provides an alternative pathway with a lower activation energy
  4. The primary sequence of amino acids

2)      What is the definition of the activation energy?

  1. All  energy used to convert the substrates to products
  2. The free energy for the reaction
  3. The highest energy needed for the reaction to occur
  4. The minimum amount of energy needed for the reaction to occur

3)      The turnover number is

  1. Represented by “kcat
  2. The number of molecules of product converted to substrate per enzyme molecule per second.
  3. The number of molecules of substrate converted to product per enzyme molecule per second.
  4. The amount of amino acid residues per turn in the α-helix

4)      Which of the following is/are correct?

  1. Co-factor:  active enzyme
  2. Apoenzyme: inactive protein part
  3. Holoenzyme : inactive protein part
  4. Co-facto: non-protein part

5)      Which of the following is/are a class of enzyme?

  1. Transferases
  2. Hydrolases
  3. Ligases
  4. Nucleases

6)      The interactions between the active site and the substrate occur via which of the following forces?

  1. Hydrogen bonding
  2. Covalent bonding
  3. Van Der Waals interactions
  4. Metallic bonding

7)      Which of the following describes enzyme specificity as being “too rigid”?

  1. The Non-Productive Binding Model
  2. Strain and Distortion
  3. Koshland’s Induced Fit Hypothesis
  4. Fischer’s Lock and Key Hypothesis

8)      Which of the following affect reaction velocity?

  1. Substrate concentration
  2. Enzyme concentration
  3. pH
  4. Pressure

9)      Which of the following is/are types of reversible inhibition?

  1. Conformational Inhibition
  2. Competitive Inhibition
  3. Irreversible Inhibition
  4. Mixed Inhibition

10)   In Noncompetitive Inhibition:

  1. Vmax is decreased
  2. Vmax remains the same
  3. Km is unchanged
  4. Km is increased

Carbs Quiz

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As my friend. the little Mexican bread up there, rightly said, this is is a fun quiz based on carbohydrates. This is just for you to review the topic, so worry not, it’s not going towards finals (lol!). Give it a go!

 

1)      Ketose sugars have a keto group at carbon:

A. 3

B. 4

C. 1

D. 6

E. 2

 

2)      Choose the correct answer from the options below:

Reactants

Products

Broken down by

A.

Glucose + Glucose

Lactose

Maltase

B.

Glucose + Fructose

Sucrose

Sucrase

C.

Glucose + Galactose

Sucrose

Lactase

D.

Glucose + Fructose

Maltose

Maltase

E.

Glucose + Glucose

Lactose

Sucrase

 

3)      Choose the TRUE answer:

A. When the concentration of glucose is high in the blood, the pancreas releases glycogen, which converts glucose to insulin.

B. When the concentration of glucose is low in the blood, the pancreas releases glucagon, which converts glycogen back to glucose.

C. When the concentration of glycogen is high in the blood, the pancreas releases insulin, which converts glucagon back to glucose.

D. When the concentration of glucose is low in the blood, the pancreas releases insulin, which converts glucose back to glycogen.

E. When the concentration of insulin is high in the blood, the pancreas releases adrenaline, which converts glucagon back to glycogen.

 

4)      Oligosaccharides are:

A. Simple sugars with multiple OH groups

B. Few monosaccharides that are covalently linked

C. 2 monosaccharides that are covalently linked

D. Polymers consisting of chains of monosaccharide units

E. Sugars with more than 2 amino acids in its structure

 

5)      Aldose sugars have an aldehyde group at carbon:

A. 1

B. 2

C. 4

D. 7

E. 3

 

6)      A chiral carbon is one that:

A. Has an OH attached to it

B. Has  phenol group attached to it

C. Has 4 different groups attached to it

D. Has an OH attached to the left of it

E. Has a double bonded O on the carbon before it

 

7)      Which of the following is a non-reducing sugar?

A. Maltose

B. Lactose

C. Glucose

D. Sucrose

E. Fructose

 

8)      The formation of a glycosidic bond is by:

A. Hydrolysis

B. Condenstation

C. Polymerisation

D. Oxidation

E. Reduction

 

9)      Lactose has a/an:

A. α-1,2 bond

B. β-1,6 bond

C. β-1,4 bond

D. α-1,4 bond

E. α-1,6 bond

 

10)  Which function BEST describes cellulose?

A. Energy source

B. Storage

C. Precursor molecule

D. Structural

E. Hydrolysis of glycosidic bonds