INTRODUCTION:

Liver is the largest organ of the body weighing 1-1.5 kg with inter dependent metabolic excretory and defence functions. It plays the major role in detoxification of various drugs, toxins like alcohol. Gamma glutamyl transferase enzyme is otherwise known as gamma glutamyl transpeptidase. It is an enzyme which is present in the liver, kidney and pancreas. Both ALP and GGT are elevated in disease of the bile ducts and in some liver diseases [1]. Some amount Iare present in other tissues. It is more sensitive enzyme compared to other enzymes like alkaline phosphatase, leucine aminopeptidase, alanine aminotransferase.

It is elevated in alcoholic cirrhosis patients and also in heavy drinkers. While previous studies have also reported increased GGT activities with increasing age. Its activity is induced by drugs namely phenytoin and phenobarbital. It is also used as a bio marker for various liver disease. Gamma glutamyl transferase plays an important role in diagnosis of early stage of liver disease in alcoholics. By this review we can associate the link between Alcohol and liver disease.

Over consumption of alcohol leads to fatty liver, alcoholic hepatitis, chronic hepatitis with liver fibrosis or cirrhosis (2) Western countries are more prone to alcoholic liver diseases due to intake of large quantity of alcoholic beverages. As far as the liver diseases are concerned, alcohol plays a crucial role in affecting the liver. Fatty liver develops in about 90% of the individuals who take more than 60 g/day of alcohol (3) Alcohol destroys liver cells. The liver breaks down alcohol to remove it completely from our body. Alcohol consumption may worsen liver injury caused by non-alcoholic liver diseases such as chronic hepatitis C. The liver has the capacity of regenerating itself. Each time when the liver filters alcohol, some of the liver cells die. The liver can develop new cells, but prolonged alcohol misuse over many years might reduce the liver’s capability to regenerate, hence it can cause a serious damage to the liver.

The reference range for gamma glutamyl transferase (GGT) is 0-30 IU/L. In most studies, males and females have equal levels, (4,5) though some studies have shown elevated GGT in males compared with females (6),usually 25% higher. Infants have 6-7 times the upper limit of the adult reference range, which declines to adult levels around age 7 months (7) GGT may be ordered along with or as a follow up to other liver function tests when a person has signs or symptoms that suggest liver disease.GGT test may is sometimes done when someone with a history of alcohol abuse has completed alcohol treatment in order to monitor compliance with the treatment program. Greater-than-normal levels of GGT may be due to Alcohol abuse, Diabetes, Flow of bile from the liver is blocked (cholestasis), Heart failure, Hepatitis, Liver ischemia (lack of blood flow), Liver necrosis, Liver tumour, Lung disease, Pancreas disease, Scarring of the liver (cirrhosis), Use of drugs that are toxic to the liver.

Mild or moderate elevation of GGT in the presence of a normal alkaline phosphatase is difficult to interpret and is often caused by changes in the liver cell enzymes induced by alcohol. GGT level are elevated in a large number of disorders that affect the drainage of bile, such as tumour blocking the common bile duct, or alcoholic liver disease or drug-induced hepatitis, blocking the flow of bile in smaller bile channels within the liver. GGT is utilized as a supplementary test to be sure that the elevation of alkaline phosphatase is indeed coming from the liver or the biliary tract. The severity of the GGT elevation is directly correlated to liver damage.

Measurement of total GGT in serum is an extraordinaryily sensitive test for disorders that affect the excretory capacity or structural integrity of the liver (8). The serum of healthy persons contains only trace amounts of GGT as compared with the tremendous activity in kidney.(9) the enzymes is the basis of tests for diseases of the liver and biliary tract(10). hepatic GGT is known to be induced by ethanol.

GGT Population Categories – Mortality Study

(Top panel unadjusted; bottom panel fully adjusted see panel margin)

Men (GGT U/L): < 15	15-19	20-29	30-49	50 or greater
Cohort Distribution: 33%	18%	18%	15%	15%
Normal Risk (NR)	NR + 46%	NR + 78%	NR + 109%	NR + 244%
Below: Data adjusted for bmi, diabetes, smoking, age, nationality, occupation group, hypertension, heart disease and alcohol
Normal Risk (NR)	NR + 26%	NR + 52%	NR + 49%	NR + 124%

CONCLUSION:

Excessive alcohol consumption is a major health problem both to serious mortility and morbidity. Serum gamma glutamyl transferase activity correlates closely with the activities of alkaline phosphatase and 5’nucleotidase in various forms of liver disease.(11). Serum GGT aims a valuable diagnostic aid when used in conjunction with ALP assays for the investigation of latent or chronic liver diseases (12). The strong correlation between serum GGT and ALP in liver, p diseases confirms that changes in the activity of GGT reflects the principally alterations in biliary function, rather than damage to the parenchymal cells (13). Enzyme induction may also account for the marked elevations of serum GGT activity in patients with alcoholic liver disease (14). Thus GGT is a valuable diagnostic aid which is used to detect the disorders linked with liver.

REFERENCES:

1. Johanna Hietala, Heidi Koivisto, Petra Antilla, Onni Neimela, comparison of the combined marker GGT –CDT and the conventional laboratory markers of alcohol abuse in heavy drinkers, moderate drinkers and abstainers, 2006, Oxford journals, volume 41, issue 5, 528-533

2. Robert. S o’ Shea, Shrinivas dasarathy, authur .j., alcoholic liver disease, 2010, hepatology, volume 51, no 1.

3. Robert. S o’ Shea, shrinivas dasarathy, Aurthur j, alcoholic liver disease, 2010, hepatology, volume 51, no 1

4. Aronsen KF, Hanson A, Nosslin. B. The value of gamma glutamyl transpeptidase in differential viral hepatitis from obstructive jaundice. A statistical comparison with alkaline phosphatase. Actachirscand, July-August 1965, 130- 92-9, medline

5. Lum. G, Gambino SR.serum gamma glutamyl transpeptidase activity as an indicator of disease of liver, pancreas or none, clinchem.aprol 1972, 18(4): 358-62. medline

6. Ruttenburg AM, Goldbarg JA, Pineda EP, erum gamma glutamyl transpeptidase activity in hepatobiliary pancreatic disease. gastroenterlogy.1963.45-43

7. Cabrera-Abreu JC, green A, gamma glutamyl transferase, value of its measurements I. Paediatrics.ann clinbiochem, jan 202, 39 :22-5

8. Elemernemenskzy and John A. Lott, gamma glutamyl transferase and its isoenzymes: progress and problem, clinical chemistry, volume 31/6, 797-803(1985)

9. Elemernemenskzy and John A.lott, gamma glutamyl transferase and its isoenzymes: progress and problem, clinical chemistry, volume 31/6, 797-803(1985)

10. P.C Sharpe, R. Mcbride and G.P.R archbold, biochemical markers of alcoholic abuse, Q. J. Med 1996.137-144.

11. Whitefield, r.e. Founder, G. Neale and D. W. Moss, serum gamma glutamyl transpeptidase activity in liver disease, gut, 1972, 702-708

12. Whitefield, R.E. Founder, G. Neale and D.W, Moss, serum gamma glutamyl Transpeptidase activity in liver disease.gut, 1972, 13, 702-708

13. Whitefield, R. E. Founder, G. Neale and D.W. Moss, serum gamma glutamyl transpeptidase activity in liver disease, gut, 1972, 13, 702-708

14. Whitefield R.E founder, G. Neale and D. W. Moss, serum gamma glutamyl transpeptidase activity in liver disease.gut 1972, 13, 702-708

Received on 13.05.2015 Modified on 15.07.2015

Research J. Pharm. and Tech. 2018; 11(1): 387-389.

DOI: 10.5958/0974-360X.2018.00070.7