Vol 4 No 4 Final.indd Althea Medical Journal. 2017;4(4) 546 AMJ December 2017 Effects of Morinda citrifolia Leaf Extract on Glucose Absorption through Intestinal Epithelial Membrane in Wistar Rat Models Rikho Melga Shalim,1 Mas Rizky A. Adipurna Syamsunarno,2 Muhammad Nurhalim Shahib2 1Faculty of Medicine Universitas Padjadjaran, 2Department of Biochemistry and Molecular Biology Faculty of Medicine Universitas Padjadjaran Abstract Background: Noni fruit (Morinda citrifolia) has been used as herbal medicine by Indonesian people. However, the effect of noni leaves as an antihyperglycemic agent is still unknown. This study was conducted to find out the effect of Morinda citrifolia leaves on glucose absorption through intestinal epithelial membrane in wistar rat models. Methods: The study was conducted in November 2015 at the Biochemistry and Molecular Biology Laboratory Faculty of Medicine, Universitas Padjadjaran. We used in situ perfusion and rats were divided into 2 groups. The first group used glucose solution as a control. The second group used glucose with extracts. Specimens were taken before and after perfusion to check the amount of glucose with spectrophotometer. Statistical analysis using t-test was conducted to compare the total absorbed concentration of glucose from each group. Results: From calculation we found the kinetic value (Km) of glucose absorption without extract (Km=17.24) and with extract (Km=16.67). Statistical test showed there was no significant in results (p>0.05). Conclusions: There is no effect of Morinda citrifolia leaf extract on glucose absorption. However, kinetics of glucose absorption suggested a non-competitive inhibition by Morinda citrifolia leaf extract. Keywords: Antihyperglycemic, glucose absorption, herbal, Morinda citrifolia, transport kinetics Correspondence: Rikho Melga Shalim, Faculty of Medicine, Universitas Padjadjaran, Jalan Raya Bandung-Sumedang Km.21, Jatinangor, Sumedang, Indonesia, Email: melgaz22_7@ymail.com Introduction Herbal medicine is a common term for people in Indonesia. Indonesian people use it for therapy purposes such as heart disease, neuronal problems, and cancer. Studies from around the world also succeed to prove the effect of herb.1,2 One of the herbs that is commonly used is Noni (Morinda citrifolia). It is a plant that grows well in Indonesia. This plant has many therapeutical effects to be used in medicating diseases.3 However, for years, the use of Noni is more likely from its fruit rather than the other part of it, the leaves. Noni leaves contain alkaloids, saponins, tannins, flavonoids, steroids, glycosides, and ascorbic acids.4 Some of them known to have effects to inhibit glucose transport in small intestine.5,6 A study was conducted and proved that saponins and flavonoids have effects in glucose transport.7 Nevertheless, the mechanism of how these chemical substances work is yet to be known. In 2010, the World Health Organization (WHO) found 10% of Indonesian people have hyperglycemic condition.8 It is a condition when blood glucose is above the normal range. This condition may cause complications that could endanger the person who bears it. Blood glucose rises because of some mechanisms including glucose transport in the small intestine. With intervention to this process, there is a possibility to overcome the hyperglycemic condition. Concentration of glucose that will be absorbed is also a decisive factor in glucose absorption. Therefore, the kinetics of glucose absorption is related to this study. Furthermore, kinetics of glucose absorption can be determined using a Lineweaver-Burk graph. By use of a millimeter block paper and scale of axis and ordinate, the researcher can calculate the kinetics value or Michaelis- Menten constant (Km). The value of Km reflects the type of inhibition from the extract.9 The purpose of this study was to find the effects of Morinda citrifolia leaves on glucose absorption through intestine and the kinetics of glucose transport in the small intestine of wistar rat. AMJ. 2017;4(4):546–52 ISSN 2337-4330 || doi: http://dx.doi.org/10.15850/amj.v4n4.1266 Althea Medical Journal. 2017;4(4) 547 Methods This study was conducted in November 2015 at the Biochemistry and Molecular Biology Laboratory, Faculty of Medicine Universitas Padjadjaran, Jatinangor. Morinda citrifolia leaves were purchased and extracted with ethanol at the Pharmacy Laboratory of Institut Teknologi Bandung (ITB). The leaves were picked from the middle part of the tree which was 2–3 years old and grown in Coblong, Bandung. Briefly, they were cut into small pieces and put in the heating and drying oven. Then, the dried leaves were mixed with ethanol 70% to undergo the maceration process. Twelve rats aged twelve to sixteen weeks old wistar rats with body weight between 200 and 250 grams were adapted for 7 days before experiment. The Health Research Ethics Committee Faculty of Medicine, Universitas Padjadjaran has agreed and gave permission to conduct this study with concern to the ethical aspects such as 3R and use of the resource equation method to calculate the number of sample needed.10,11 There were conditions to be met before the rats were going to the experiment. These conditions were the inclusion and exclusion criteria. The rats must be in healthy conditions without wounds, and active. There were also some conditions that excluded the rats to be used further such as a dropped in weight more than 10% after the adaptation period and if the rats had been used in an experiment before. The glucose absorption was measured by in situ perfusion technique to make sure every rat in each group was given the same amount of glucose. Then, the rats were fasted and anesthetized by Ketamine with dosage of 0.13 mg/100 gram body weight. After the anesthesia has worked, the abdomen was opened to install cannulas at 10 cm after pylorus and 25 cm from the first cannula with a marked string to help measure the length of intestine. Next step, each cannula was connected with a rubber tube to bath the intestine with solutions. Furthermore, the rats were divided into 2 groups. The first group was the control group which was given glucose solution, while the second group was given glucose with Morinda citrifolia leaf extract solution. The intestine was perfused with 2.5, 5, and 10 mmol for every 15 minutes with and without leaf extract. Pre and post perfused solution were collected at the end of perfusion process. The solutions were mixed with aquadest and trichloroacetic acid (TCA) 8% and centrifuged for 10 minutes at 3000 rpm. To obtain the best result, the solutions were incubated in 37oC for 10 minutes or at room temperature for 25 Figure 1 Rat with Perfusion Set Rikho Melga Shalim, Mas Rizky A. Adipurna Syamsunarno, Muhammad Nurhalim Shahib: Effects of Morinda citrifolia Leaf Extract on Glucose Absorption through Intestinal Epithelial Membrane in Wistar Rat Models Althea Medical Journal. 2017;4(4) 548 AMJ December 2017 Table 1 Absorption Data of Control Group Solution Rat Time Absorbancy Remaining Glucose (mg/dL) Absorbed Glucose (mg/dL) Mean ± Standard Deviation G1 1 Before 0.045 35.71 4.76 11.11 ± 4.788 After 0.039 30.95 2 Before 0.043 34.13 14.29 After 0.025 19.84 3 Before 0.044 34.92 17.46 After 0.022 17.46 4 Before 0.044 34.92 7.14 After 0.035 27.78 5 Before 0.045 35.71 9.52 After 0.033 26.19 6 Before 0.039 30.95 13.49 After 0.022 17.46 G2 1 Before 0.130 103.17 46.83 36.77 ± 9.585 After 0.071 56.35 2 Before 0.134 106.35 44.44 After 0.078 61.90 3 Before 0.133 105.56 44.44 After 0.077 61.11 4 Before 0.131 103.97 24.60 After 0.100 79.37 5 Before 0.134 106.35 28.57 After 0.098 77.78 6 Before 0.131 103.97 31.75 After 0.091 72.22 G3 1 Before 0.254 201.59 57.94 56.08 ± 8.364 After 0.181 143.65 2 Before 0.254 201.59 64.29 After 0.173 137.30 3 Before 0.257 203.97 65.87 After 0.174 138.10 4 Before 0.239 189.68 43.65 After 0.184 146.03 5 Before 0.240 190.48 53.17 After 0.173 137.30 6 Before 0.241 191.27 51.59 After 0.176 139.68 Note: Solution G1=Glucose 2.5 mmol; G2=Glucose 5 mmol; G3=Glucose 10 mmol Althea Medical Journal. 2017;4(4) 549Rikho Melga Shalim, Mas Rizky Anggun Adipurna Syamsunarno, Muhammad Nurhalim Shahib: Effects of Morinda citrifolia Leaf Extract on Glucose Absorption through Intestinal Epithelial Membrane in Wistar Rat Models Table 2 Absorption Data of Experimental Group Solution Rat Time Absorbancy Remaining Glucose (mg/dL) Absorbed Glucose (mg/dL) Mean ± Standard Deviation M1 1 Before 0.045 35.71 17.46 14.02 ± 4.935 After 0.023 18.25 2 Before 0.047 37.30 22.22 After 0.019 15.08 3 Before 0.046 36.51 11.90 After 0.031 24.60 4 Before 0.046 36.51 12.70 After 0.030 23.81 5 Before 0.041 32.54 11.11 After 0.027 21.43 6 Before 0.037 29.37 8.73 After 0.026 20.63 M2 1 Before 0.089 70.63 42.06 21.83 ± 17.072 After 0.036 28.57 2 Before 0.092 73.02 43.65 After 0.037 29.37 3 Before 0.094 74.60 19.05 After 0.070 55.56 4 Before 0.109 86.51 10.32 After 0.096 76.19 5 Before 0.092 73.02 12.70 After 0.076 60.32 6 Before 0.094 74.60 3.17 After 0.090 71.43 M3 1 Before 0.219 173.81 61.90 51.85 ± 9.546 After 0.141 111.90 2 Before 0.221 175.40 65.87 After 0.138 109.52 3 Before 0.233 184.92 46.83 After 0.174 138.10 4 Before 0.235 186.51 46.03 After 0.177 140.48 5 Before 0.236 187.30 47.62 After 0.176 139.68 6 Before 0.223 176.98 42.86 After 0.169 134.13 Note: Note: Solution M1=Glucose 2.5 mmol + Morinda citrifolia leaves; M2=Glucose 5 mmol + Morinda citrifolia leaves; M3=Glucose 10 mmol + Morinda citrifolia leaves Althea Medical Journal. 2017;4(4) 550 AMJ December 2017 minutes. The absorbance data were analyzed with the spectrophotometer in 505 nm wave length. Next, the data were calculated and analyzed using independent t-test to compare data with and without Morinda citrifolia leaf extract solution, with significant values of p<0.05. On the other side, kinetics calculation was not using computerized tools or applications. This study used a millimeter block paper to draw a graph of Lineweaver-Burk with 1/S (S=concentration of glucose) on axis and 1/V (V=velocity of absorption which was equal to the amount of absorbed glucose). There were 2 lines to be drawn, control (G) and experimental (M). For the axis, 1 smallest square equals to 0.002/mmol, and the ordinate, 1 smallest square equals to 0.0001/mg. Then we took the point of both intersections with axis and use it as a value of -1/Km. Results Results from this study showed that in glucose with 2.5 mmol concentration, the addition of Morinda citrifolia leaf extract was not providing much difference in the mean of absorbed glucose. In fact, data of the solution with extract had 2.91 mg/dL more higher absorbed glucose than the solution without Figure 2 Glucose Concentration Figure 3 Graph of Lineweaver-Burk9 Althea Medical Journal. 2017;4(4) 551 extract (Table 1). A difference was found in 5 mmol of glucose concentration. The mean of absorbed glucose in the control group was 14.94 mg/dL much more than in the group with extract. There was also a difference in 10 mmol glucose concentration with extract, since the mean of absorbed glucose was 4.23 mg/dL less than in the control group (Table 2). The rise of glucose absorption following the increase of glucose concentration showed the red line, which represented glucose with extract, mostly had a position below the blue one, which represented glucose only solution. There was no significant effects of Morinda citrifolia leaf extract in glucose absorption (Figure 2). Next, we calculated the kinetics of glucose transport with and without Morinda citrifolia leaves which showed that the one without additional extract had value of -1/Km=-0.058. Therefore, the Km=17.24. The second, which was glucose with extract, had value of -1/ Km=-0.06 and made the Km=16.67 (Figure 3). Discussions Moreover, a statistical test was performed and found there was not any significant results in glucose concentration with p value 0.324 (2.5 mmol); 0.091 (5 mmol); and 0.433 (10 mmol). Although in two concentrations of glucose showed that there were decreases in glucose absorption,the statistical test gave insignificant results. This may occur with reasons such as the occurrence of a different antihyperglycemic mechanism. A previous study showed Morinda leaves have two antihyperglicemic mechanisms, by increasing the production of insulin and increasing the peripheral utilization of glucose.12 There were also limitations in this study. The variety of each rat’s ability to absorb glucose should be considered which took part in varies results. In addition, the insulin also took part in glucose absorption from the cell into bloodstream.13 It can be concluded that there is no effect of Morinda citrifolia leaf extract on intestine glucose absorption in wistar rats which is shown by statistical test results with p values >0.05. On the other hand, the kinetic results show a little difference in Km values, which mean the inhibitor, is not interfered by the glucose transport in the absorption process. 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