The effect of lecithin on liver function of white rats (Rattus norvegicus) induced carbon tetrachloride

BIOMEDICAL ENGINEERING BE

  journal homepage: be.ub.ac.id The effect of lecithin on liver function of white rats (Rattus norvegicus) induced carbon tetrachloride ₁

  † ₁ Lestari Dewi Faculty of Medicine, Hang Tuah University, Surabaya, East Java, Indonesia

  A R T I C L E I N F O A B S T R A C T

Article history: Objective: To prove that the lecithin is administered orally has hepatoprotective effect on white male rats given

Received CCl4 intraperitoneally.

  

Accepted Material and Methods: 45 male Wistar rats, aged 12 weeks were randomly divided into five groups. Group I,

given solvent CMC - Na 0.25% dose of 0.01 ml/g bw, and were given olive oil dose of 1 ml/kg bw, intraperitoneal Available online injection. Group II, given solvent CMC - Na 0.25% dose of 0.01 ml/g bw, and given CCl4 dose of 1 ml/kg bw,dissolved in olive oil by intraperitoneal injection. Group III, IV and V respectively given dose lecithin Keywords:

  

Lecithin, 90/180/360 mg/ kg bw,dissolved with 0.25% CMC-Na, and given CCl4 dose of 1 ml/kg bw dissolved in olive oil at

a ratio of 1: 1, by intraperitoneal injection. On day 10, 24 hours after administration of CCl4 and olive oil , all the _† Carbontetrachloride rats dissected, after first anesthetized with ether by inhalation. Then the blood taken from the heart to examine Corresponding author: the level of AST and ALT in serum and hepar were taken for histopathological examination. dr_lestari@yahoo.co.id

  Results: Giving lecithin 90/180/360 mg/kg bw were accompanied CCl4 1 ml / kg body weight (group III, IV, and V), shown to reduce levels of SGOT in serum compared with the group that received only CCl4 and giving lecithin 90/180/360 mg/ kg bw with CCl4 1 ml/kg bw (group III, IV, and V) is proven to reduce ALT levels compared with the group that received only CCl4. On histopathological examination of liver cells proves that lecithin dose 90 / 180/360 mg/kg bw with CCl4 1 ml/kg bw is proven to reduce the amount of cell necrosis than the group that only received CCl4.

  Conclusion: Lecithin has a protective effect against the liver function _.

  homocysteine levels [4], and improve brain memory in patients with Alzheimer's, and Indonesia with the biological natural dementia in patients with Parkinson's [4, 8, 13, 30, resources, has a variety of plant species is 31, 33]

  1. Introduction

  ”. Lecithin is also an important ingredient efficacious as a traditional medicine. One of them formation of neurotransmitters [9, 34] ”. Oral is the soybean plant. Since the first, the intake of lecithin may also help reduce the community has been utilizing soybean plants as a formation and healing of gastrointestinal ulcers in food ingredient Indonesia, as one of the countries some animal species [30] ”. Of various dietary producing soybeans, soybean processed products supplement products contained in the free have become daily consumption, among other market, there are products that contain lecithin, dishes processed into tofu and tempe, and soy derived from soy beans. The product is recognized milk. Communities also use soy as a traditional to cure various diseases caused by free radicals, medicine. Soybeans have been widely recognized including hepatic dysfunction. Lecithin is a and exploited as a source material of lecithin substance that turned out to have antioxidant [2,56] ”. Soybean oil contains a substance called effects [2, 3] ”. In an in vitro study results obtained, lecithin (4)”. For decades, lecithin has been that the soybean oil (soybean oil) contain the popular used for treatment of various diseases, highest levels of antioxidants among plant oils including lowering cholesterol levels in serum [4, derived from seeds [24]

  ”. That is why lecithin 17, 20, 27, 35, 36, 38] ”, lowering plasma from soybeans more potent as compared lecithin

  

Please cite this article as: Dewi,L. The effect of lecithin on liver function of white rats (Rattus Norvegicus) Induced Carbon

  

Please cite this article as: Dewi,L. The effect of lecithin on liver function of white rats (Rattus Norvegicus) Induced Carbon

  cholesterol lowering of corn oil [25] ”. Since several decades, the role of antioxidants for health has been a lot of attention from the scientific community. Hundreds of studies have been conducted and published. Physiological function of antioxidants is to prevent further damage to cellular components as a result of chemical reactions involving free radicals. Free radical production occurs continuously in all cells as part of normal cellular function. If there is excessive production of free radicals will cause oxidative stress [16]. Oxidative stress plays an important role in the pathophysiology of various diseases, including atherosclerosis, inflammatory processes, cancer, chronic renal failure, and diabetes mellitus as well as the aging process [16, 18] ”. Oxidative stress also causes a major pathogen in liver disorders [22] ”. Repair of fatty degeneration, fibrosis, and cirrhosis can be achieved primarily by antioxidants or agents that neutralize the collagen deposition [23] ”. The liver is an organ that plays an important role in the metabolism and detoxification. Exposure by a variety of toxic materials will enhance liver damage . Potential liver damage because it is the first organ of the gastrointestinal tract after exposure to the materials - materials that are toxic. The process of metabolism by the liver to detoxify the Raw-material, but the process can produce metabolites that are more toxic than the parent material [5] ”. Materials - materials that are toxic to the liver can be derived from the food we eat. Along with the advancement of civilization and technology, developments in the field of processed foods have also increased. To make food more attractive appearance, taste better, and are more durable that required certain materials are added to the food. Material - extra material is not seldom that are toxic to the liver. In addition, the drug - a drug that is used freely, not by the rules or prescribed dose, can also toxic effect on the liver [26] ”. In this study, a model of liver disease, use induction potent hepatotoxins, namely carbon tetrachloride (CCl4) in experimental animals [1, 5, 18, 23, 28, 29] ”. CCl4 is a prototype hepatotoxic substances most commonly used in research related to hepatotoxicity, because in small doses has a clear effect, available in pure form and can give the same effect on different species, and when given orally can cause liver damage more severe compared with other organs [11, 21] ”. Liver damage caused by CCl4 is due to exposure to free radicals

  [30] ”. Based on the above background, the activity of soybean lecithin can protect liver function with the possibility of working as an antioxidant. So in this study to prove whether lecithin from soybeans, which is administered orally to male white rats that had been induced with CCl4, has a hepatoprotective effect, by measuring the levels of AST and ALT enzymes and liver histopathology. From the results of this research can obtain information and useful scientific data on the effect of lecithin on the liver.

  2. Materials and Methods

  The research design used was a type of research "true experimental" by using the method: Randomized, the post-only control group design. A total of 45 rats were randomly divided into five treatment groups, each consisting of 9 rats and adapted for 1 week prior to the study. Group I: Given a solvent CMC - Na 0.25% dose of 0.01 ml / g body weight, the intragastric sonde, single dose, every day, for 9 days. On day 9, 4 hours after administration of CMC-Na 0.25%, rats were given olive oil dose of 1 ml / kg body weight intraperitoneal injection. 24 hours later surgery. Group II given solvent CMC - Na 0.25% dose of 0.01 ml / g body weight, the intragastric sonde, single dose, every day, for 9 days. On day 9, 4 hours after administration of CMC-Na 0.25% , rats given CCl4 dose of 1 ml / kg body weight dissolved in olive oil at a ratio of 1: 1, by intraperitoneal injection. 24 hours later surgery. Group III: Given lecithin dose of 90 mg / kg body weight dissolved in CMC-Na 0.25% , the intragastric sonde, single dose, every day, for 9 days. On day 9, 4 hours after administration of a dose of 90 mg lecithin / kg body weight, rats given CCl4 dose of 1 ml / kg body weight dissolved in olive oil at a ratio of 1: 1, by intraperitoneal injection. 24 hours later surgery. Given lecithin group IV dose 180 mg / kg body weight dissolved in CMC-Na 0.25%, the intragastric sonde, single dose, every day, for 9 days. On day 9, 4 hours after administration of lecithin dose 180 mg / kg body weight, rats given CCl4 dose of 1 ml / kg body weight dissolved in olive oil at a ratio of 1: 1, by intraperitoneal injection. 24 hours later surgery. Group V Given lecithin dose 360 mg / kg body weight dissolved in CMC-Na 0.25%, the intragastric sonde, single dose, every day, for 9 days. On day 9, 4 hours after administration of a dose of 360 mg lecithin / kg body weight, rats

2.1 Animal Etic Code

  

Please cite this article as: Dewi,L. The effect of lecithin on liver function of white rats (Rattus Norvegicus) Induced Carbon

  given CCl4 dose of 1 ml / kg body weight dissolved in olive oil at a ratio of 1: 1, by intraperitoneal injection. 24 hours later surgery.On day 10, ie 24 hours after administration of CCl4 and olive oil and, all rats dissected, after first anesthetized with ether by inhalation. Then the blood taken from the heart as much as 3 ml .Serum obtained was used as a sample for AST and ALT. Liver take in 10% formalin, then checked the histopatology.

  Animal was placed in a plastic box, measuring 50 x 40 cm, woven wire topped lid. Each box contains 5 rats. The boxes are then placed on a shelf plastic stacking timber, and placed in a room with lighting conditions, air circulation, good hygiene. Each was given a plastic box base from the chaff, with the aim of absorbing urine, so it does not wet the body, which can affect their health. The husks replaced every day. Plastic box also changed and washed every day. Food and beverages provided ad libitum.Giving lecithin and CMC-Na orally, performed using the sonde pediatric hose No. 8, directly into the stomach.

  Administration of CCl4 and olive oil by intraperitoneal injection performed using tuberculin syringe. Before the surgery, animal anesthetized with inhaled ether. Animal anesthetized for approximately 1 minute, by the way put in a jar containing cotton that has been moistened with ether. Animals taken not to die. Then performed surgery on his abdomen using scissors, and the first organ to look for is heart. This surgical procedure is done carefully so that the scissors are not the inferior vena cava. In a state still anesthetized, the heart was still in pulsed conditions, then with 5 cc syringe of blood taken from the heart, aspirated with a syringe for up to 3 cc. Then the liver organ is taken for histopathological examination.

  3. Result

  The following table shows the effect of lecithin dose of 90, 180, and 360 mg / kg body weight /day, the intragastric for 9 days on levels of AST, ALT and liver histopathology white male rats (Rattus

  norvegicus) induced CCl4 dose of 1 ml / kg, single dose , intraperitoneally.

  

Table 1. The effect of lecithin dose of 90, 180, and 360 mg / kg body weight /day on the intragastric for 9 days on levels of AST, ALT and liver

histopathology of white male rats No Group Level of AST (X  SD) ( U/L) Kadar ALT (X  SD) ( U/L ) Mean of Rank

  1 I 173,89  34,92 68,89  9,62 14,00

  2 II 541,89  226,23 233,44  109,39 29,00

  3 III 486,78  407,43 225,00  212,92 29,00

  4 IV 488,11  296,46 234,33  171,09 26,50

  5 V 458,78  191,41 199,22

   134,73 16,50

  In the results of the study proved that the administration of CCl4 1 ml / kg increase AST levels were significantly different (P <0.05) compared to controls. Giving lecithin 90, 180, and 360 mg / kg were accompanied CCl4 1 ml / kg proven to reduce levels of AST in serum compared with the group that received only CCl4 alone, although there was no significant difference, but there is a tendency that increasing the dose of lecithin is given, then the levels of AST decreased. Results of research on the effect of lecithin on levels of ALT, also proves that the administration of CCl4 can increase ALT levels were significantly different (P <0.05) compared to controls. Giving lecithin 90, 180, and 360 mg / kg CCl4 with 1 ml / kg proven to reduce ALT levels compared with the group that received only CCl4 , although there was no significant difference, but there is a tendency that increased dosage of lecithin is given, the levels of ALT decline. In the administration of lecithin dose 360 mg / kg CCl4 with 1 ml / bw, obtained proven ALT levels not significantly different from the control group. Linear regression analysis proved that there is a linear relationship in the group given lecithin with ALT levels, namely a decrease in serum ALT levels with increasing doses of lecithin are given. On histopathological examination of liver cells proved that administration of CCl4 1 ml / kg caused an increase in the number of cells undergoing necrosis with a highly significant difference (P <0.01) compared with controls, and

  

Please cite this article as: Dewi,L. The effect of lecithin on liver function of white rats (Rattus Norvegicus) Induced Carbon

  significantly different (P <0.05) than the group that received lecithin 360 mg / bw. Giving lecithin doses 90, 180, and 360 mg / kg CCl4 with 1 ml / kg proven to reduce the number of necrotic cells than the group that only received CCl4, and there is a tendency that increased dosage of lecithin is given, the amount of cell necrosis decline. Linear regression analysis proved that there is a linear relationship in the group given lecithin with histopathological changes in the liver cells, namely a decline in the number of liver cells that undergo necrosis with increasing doses of lecithin are given.

4. Discussion

  Carbon tetrachloride (CCl4) is a chlorinated hydrocarbon, which has been widely used in research as an inducer of hepatic damage caused by free radicals. The involvement of free radicals in the pathogenesis of liver damage caused by CCl4 toxicity has been studied and widely recognized [1, 18, 23, 28, 29]. In the liver, CCl4 requires biotransformation by cytochrome P450 to produce a metabolite that is more toxic free radicals, and more reactive, namely trichloromethyl free radical (CCl3 ●). Trichloromethyl free radical will react with polyunsaturated fatty acids (PUFAs) by taking the hydrogen ions. Reaction with the PUFA initiated the process of lipid peroxidation [11, 12, 23]

  ”. Lipid peroxidation causes dysfunction of the liver cell membrane and form a reactive aldehyde. Furthermore, both of these will cause damage to hepatocytes, and can ultimately lead to cell death (necrosis) [23]

  ”. In this study, to know there has been a disruption CCl4-induced hepatic function then performed biochemical and histopathological examination. Damage to the liver will be marked by the release of enzymes found in the liver into the circulation. The liver is made up of thousands of enzymes, some of which are present in low concentrations in serum. If an increase in enzyme activity in serum, it showed increased serum levels are included in the result of damage to liver cells [7]. Elevated levels of AST and ALT enzymes in the blood circulation can be used as an indicator of hepatic disorders [10] ”. AST and ALT testing as an indication of liver damage so far proved the most practical and the most frequently used [10,14] ”. In this study demonstrated that in rat that received CCl4 induced increased levels of AST and ALT enzymes in the serum. Rat blood serum test results above are supported by histopathological examination of the liver. As has been described previously that induction of CCl4 will cause necrosis of liver cells. The greater the dose of lecithin is given, then the enzyme levels in the serum AST and ALT decline and the number of necrotic cells decreased. From the results of the study it can be concluded that lecithin administration in rat is proven to protect against CCl4-induced hepatotoxicity. How does the mechanism of action of lecithin so as to prevent hepatotoxicity of CCl4? Mechanism of lecithin protection against CCl4 induced hepatotoxicity is its role as an antioxidant. CCl4- induced hepatotoxicity can be overcome with a material that is as an antioxidant, inhibiting free radicals and anti-lipid peroxidation [4, 17, 18, 33] ”. The antioxidant activity in inhibiting free radical exposure is very important in protecting liver damage [29] ”. In previous studies it is known that lecithin from soy beans turned out to be a substance that has antioxidant effects [2,3] ”. And in a study of the results obtained in vitro, that the soybean oil (soybean oil) contain the highest levels of antioxidants among plant oils derived from seeds [24] ”. In addition, Semra Demirbilek and colleagues (2004), has been conducting research to determine the effect of lecithin treatment on levels of Malondialdehyde (MDA) were made septic rat liver, lecithin shown to lower hepatic MDA concentration. MDA is a metabolite produced by lipid peroxidation. With its role as an antioxidant, lecithin can prevent, or reduce the occurrence of lipid peroxidation process. If the lipid peroxidation can be prevented or reduced, then the damage and cell death can be prevented or reduced. In addition to the antioxidants, lecithin another mechanism of protection against hepatotoxicity caused by the material it contains. As we know, the main content of lecithin is phosphatidylcholine. Phosphatidylcholine is the main constituent component of cell membranes and play an important role in regulating the homeostasis of membrane fluidity. Resulted in the disruption of lipid peroxidation of cell membrane function. With that contains phosphatidylcholine, lecithin can improve the function of the cell membrane are disturbed by improving the integrity of the membrane, so that the liver cell membrane dysfunction can be prevented, and necrotic cells can be inhibited. With the advance of lecithin therapy, the expected damage of liver cells that have occurred previously can be repaired, and liver cells is again in a state of

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Please cite this article as: Dewi,L. The effect of lecithin on liver function of white rats (Rattus Norvegicus) Induced Carbon

  "steady state", so that when induced with CCl4, liver cells will experience severe interference experimental animals that did not receive therapy previous lecithin.

  5. Conclusion

  The results of this study it can be concluded that lecithin has a protective effect against the occurrence of elevated levels of AST and ALT enzymes in the serum, and liver cell damage in rats induced by carbon tetrachloride.

  Acknowledgment

  This research was conducted thanks to the Community Fund Grant from the Faculty of Dentistry Universitas Gadjah Mada.

  Conflict of Interest

  The authors report no conflicts of interest

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