Correlation between Adiponectin Receptor (AdipoR) with

Homeostatic Model Assessment for Insulin Resistance (HOMA-IR),

Peroxisome Proliferator-Activated Receptor Gamma (PPAR-ϒ), and

p38-mitogen-activated protein kinases (MAPK) in

Type 2 Diabetic Rats Treated with Puguntano

(Turanga feel-terrae Lour.) Leaves Extract

Dharma Lindarto

, Melati Silvani Nasution

, Santi Syafril

, Awaluddin Saragih

Department of Internal Medicine, Faculty of Medicine, Universitas Sumatera Utara, H. Adam Malik General Hospital,

Medan, Indonesia;

Department of Pharmacology and Therapeutic, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia.

Keywords: T2DM, HOMA-IR, PPAR-ϒ, p38-MAPK, Puguntano (Curanga fel-terrae Lour.)

Abstract: Adiponectin has a role in regulating metabolic processes, anti-inflammation, and insulin sensitizers. This

study aimed to examine the correlation between adiponectin receptor (AdipoR) with FPG, insulin, HOMA-

IR, PPAR-ϒ, and p38MAPK in rats model of T2DM. A total of 48 Wistar rats aged 8-10 weeks with a

weight of 180-200 grams were selected. The Wistar rats were induced into T2DM by feeding high-fat

(HFD) diet and injecting small doses of streptozotocin (STZ) 30 mg/kg.bw. The Wistar rats were then

divided randomly into 2 groups: control group (n=24) and treatment group (n=24). The treatment group was

given puguntano leaves extract at a dose of 200 mg/kg. BW once daily for 10 days. After that, AdipoR,

FPG, insulin, HOMA-IR, PPAR-ϒ, and p38MAPK levels were examined. FPG, insulin, and HOMA-IR

levels were significantly lower, but p38MAPK and AdipoR levels were significantly higher in the treatment

group than in the control group. In the group of all subjects, there was a significant correlation between

AdipoR with FPG, insulin, HOMA-IR, PPAR-ϒ and p38MAPK (r=-0.536, p=0.000**, r=-

0.416, p=0.003**; r=-0.478, p=0.001**; r=0.587, p=0.000**; respectively). There was a significant

correlation between AdipoR with the characteristic of insulin resistance (HOMA-IR) and pathways of post-

receptor insulin (PPAR-ϒ and p38MAPK).

1 INTRODUCTION

Adiponectin is widely known as an insulin sensitizer

based on its identification, characterization, and

underlying mechanisms. Adiponectin can reduce

plasma glucose level of rats by suppressing liver

glucose production or increasing glucose uptake in

the peripheral which is independent of insulin (Berg

et al, 2001) inhibiting phosphoenolpyruvate

carboxykinase, glucose-6-phosphatase expression

(Yamauchi et al, 2002), 5'-AMP-activated protein

kinase (AMPK), thereby improving insulin

resistance and preventing hepatosteatosis (Liu et al,

2012). Based on other studies, giving adiponectin

will increase fatty acid oxidation in the skeletal

muscle thereby reducing the content of triglycerides

in muscles and liver and increasing insulin

sensitivity in vivo (Yamauchi et al, 2001).

Adiponectin suppresses the inflammatory response

to macrophages in the tissue (Iannitti et al, 2015).

The effect of adiponectin is mediated by

adiponectin receptors namely AdipoR1 and

AdipoR2 by regulating the expression of metabolic

genes and insulin sensitivity in the target tissue of

insulin (Yamauchi et al, 2007). The expression of

both adiponectin receptors increases fatty acid

oxidation, decreases liver triglyceride levels,

improves insulin resistance, modulates food intake

and energy expenditure, and reduces inflammation.

There is a correlation between mRNA expression

from adiponectin receptors and adiponectin

(Yamauchi et al, 2007; Yamauchi and Kadowaki,

Lindarto, D., Nasution, M., Syafril, S. and Saragih, A.

Correlation between Adiponectin Receptor (AdipoR) with Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Peroxisome Proliferator-Activated Receptor Gamma (PPAR-),

and p38-mitogen-activated protein kinases (MAPK) in Type 2 Diabetic Rats Treated with Puguntano (Turanga feel-terrae Lour.) Leaves Extract.

DOI: 10.5220/0009855900520055

In Proceedings of the 2nd International Conference on Tropical Medicine and Infectious Disease (ICTROMI 2019), pages 52-55

ISBN: 978-989-758-469-5

2008). According to previous studies, administration

of the ethanol extract of puguntano leaves (C. feel-

terrae [Lour.]) can significantly improve glucose

metabolism and insulin resistance and increase

adiponectin (Lindarto et al, 2016) and adiponectin

receptor (Lindarto et al, 2019), p38 mitogen-

activated protein kinase (MAPK) levels and GLUT-

4 expression (Syafril et al, 2019) in the treatment

group than in the control group.

The aim of this study was to investigate the

correlation between adiponectin receptor with

fasting plasma glucose (FPG), insulin, homeostatic

model assessment for insulin resistance (HOMA-

IR), peroxisome proliferator-activated receptor

gamma (PPAR-ϒ), and p38 MAPK in T2DM Wistar

rats treated with puguntano leaves extract.

2 METHODS

The study used 48 male Wistar rats aged 8-10 weeks

with a weight of 180-200 grams. Rats were placed

under the natural light cycle at a temperature of 22-

25°C. The Wistar rats were induced T2DM by

feeding HFD for 5 weeks, followed by

intraperitoneal STZ injections 30 mg/kg.BW (

Sigma-Aldrich, Munich, Germany). FPG was

measured from the blood of the lateral tail vein using

a glucometer in which FPG > 200 mg/dL was

considered T2DM (Zhang et al, 2008). Rats were

divided randomly into two groups (control group,

n=24, and treatment group, n=24). The treatment

group was given ethanol extract of puguntano leaves

200 mg/kg.bw/day for 10 days using an orogastric

cannula. The control group was sacrificed when was

diagnosed with T2DM, while the treatment group

was sacrificed after 10 days of treatment. The

sacrifice was done by administering anesthesia

(ketamine), and the head of the rats was beheaded.

After the blood was collected from the left ventricle,

FPG (spectrophotometry) and fasting insulin

(sandwich ELISA) were examined.

Skeletal muscle samples were processed by

homogenization in a cold homogenizing buffer (-

80°C) which was used to determine the level of p38-

mitogen-activated protein kinases (MAPK), PPAR-

ϒ, and AdipoR with Qayeebio kit (China).

The research was conducted at the Molecular

Genetics Laboratory, Faculty of Medicine,

Universitas Padjadjaran Bandung. The ethanol

extract of puguntano leaves was obtained by

maceration method in the Department of Biological

Pharmacy, Faculty of Pharmacy, Universitas

Sumatera Utara, Medan, Indonesia (Kemenkes RI,

2013). This research has been approved by the

Ethics Committee of the Universitas Sumatera

Utara, Medan, Indonesia (Reference 42 / TGL /

KPEK FK USU-RSUP HAM / 2018).

Statistical analysis was performed using SPSS

22.0 software. All data are expressed as a

meanstandard deviation. The Wilcoxon test was

used to compare non-normally distributed groups,

while the Pearson’s or Spearman’s test was used for

the correlation test. A p-value < 0.05 indicated a

statistically significant difference.

3 RESULTS

In Table 1, the FPG, Insulin, HOMA-IR, PPAR, and

p38-MAPK levels in the control group had a

significant difference with the treatment group.

Table 1. Characteristic Baselines of Subjects

Characteristic

Group

All subjects (n=48)

MeanSD

Control (n=24)

(MeanSD)

Treatment (n=24)

(MeanSD)

FPG (mg/dl)

256.10153.68 375.58



29.15 136.63



33.62

0.000**

Insulin

54.645.58 57.36



6.28 52.32



3.32

0.001**

HOMA-IR

1.951.17 3.05



0.51 0.86



0.20

0.000**

PPAR-ϒ(ng/mL)

35.187.46 29.56



1.06 40.80



6.83

0.000**

p38-MAPK (ng/mL)

22.253.82 20.81



3.02 23.70



4.04

0.005**

AdipoR (ng/mL)

15.223.21 13.79



1.47 16.64



3.83

0.000**

Data are expressed as a mean  standard deviation; Wilcoxon test.

: Control Group vs Treatment Group;

FPG: fasting plasma glucose; HOMA-IR: Homeostatic Model Assessment for Insulin Resistance; PPAR-ϒ;

Peroxisome Proliferator-Activated Receptor-ϒ; p38-MAPK: p38 mitogen-activated protein kinase.

*: < 0.05; **: <0.01.

Correlation between Adiponectin Receptor (AdipoR) with Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Peroxisome

Proliferator-Activated Receptor Gamma (PPAR-), and p38-mitogen-activated protein kinases (MAPK) in Type 2 Diabetic Rats Treated with

Puguntano (Turanga feel-terrae Lour.) Leaves Extract

Table 2. shows that AdipoR in all subject group

significantly correlated with insulin, HOMA-IR, and

PPAR-ϒ, whereas there was no correlation found in

the control and treatment groups, except for p38-

MAPK.

Table 2. Correlation between AdipoR with HOMA-IR, PPAR-ϒ, and p38-MAPK in all groups

Characteristic

Group

All subjects (n=48) Control

(n=24)

Treatment

(n=24)

r p r p r p

FPG (mg/dl) -0.536 0.000** -0.274 0.196 -0.264 0.212

Insulin -0.416 0.003** 0.024 0.912 -0.402 0.052

HOMA-IR -0.478 0.001** -0.033 0.878 -0.254 0.231

PPAR-ϒ (ng/mL) 0.587 0.000** 0.088 0.680 0.578 0.003**

p38-MAPK (ng/mL) -0.063 0.670 -0.334 0.106 -0.273 0.197

Data are expressed as mean  standard deviation; Wilcoxon test.

: Group 1 vs Group 2; FPG: fasting

plasma glucose; HOMA-IR: Homeostatic Model Assessment for Insulin Resistance; PPAR-ϒ;

Peroxisome Proliferator Activated Receptor-ϒ; p38-MAPK: p38-mitogen-activated protein kinase.

*: < 0.05; **: <0.01.

4 DISCUSSION

Secondary metabolites of the ethanol extract of

puguntano leaves identified were glycosides (Zhou,

2005), flavonoids (Huang, 1998), saponins (Fang et

al, 2009), and terpenoids (Wang et al, 2006), which

can decrease blood sugar levels by stimulating the

production and secretion of insulin. Tannin increases

glucose uptake via insulin signaling pathways such

as phosphoinositide 3-kinase (PI3K), p38-MAPK,

and GLUT-4 translocation (Kumari and Tannins,

2012). AdipoR improves glucose metabolism

through mechanisms such as increases fatty acid

oxidation in the muscles and suppresses lipid

cumulation in the liver by activating AMPK so that

the content of triglycerides in the liver and muscles

decreases and insulin sensitivity is improved

(Yamauchi et al,2001).

Adiponectin can stimulate the improvement of

the p38-MAPK pathway (Mao et al, 2006) as an

anti-inflammatory effect (Xin et al, 2011) and the

enhancement of PPAR-ϒ expression through

increasing 3T3-L1 cells associated with

differentiation of adipocytes (Fu et al, 2005).

Adiponectin in diabetic patients had a significant

negative correlation with BMI and positive

correlation with systolic blood pressure and

microalbuminuria (El Dayem et al, 2015).

In this study, treatment with puguntano

significantly improved FPG, insulin, HOMA-IR,

PPAR-ϒ, p38-MAPK, and AdipoR. The increase in

adiponectin receptor correlates significantly with

insulin, HOMA-IR, and PPAR-ϒ in all subjects

groups.

Conclusion: Puguntano treatment reduces the

risk of cardiovascular diseases, while an increase in

adiponectin receptor is associated with improved

insulin resistance (HOMA-IR) and post-receptor

insulin (PPAR-ϒ and p38-MAPK). In addition to

insulin sensitivity and post-receptor insulin,

adiponectin and AdipoR has various working

mechanisms.

ACKNOWLEDGMENT

The authors acknowledge the assistance of the

Molecular Genetics Laboratory, Faculty of

Medicine, Universitas Padjajaran, Bandung.

CONFLICT OF INTEREST

The author stated that there is no conflict of interest

regarding the publication of this article

REFERENCES

Berg AH, Combs TP, Du X, Brownlee M, Scherer PE,

2001. The adipocyte-secreted protein Acrp30

enhances hepatic insulin action. Nat. Med. 7(8):947-

53.

El Dayem SMA, Nazif HK, EI-Kader MA, El-Tawil M.

Study of Adiponectin Level in Diabetic Adolescent

Girls in Relation to Glycemic Control and

Complication of Diabetes. OA Maced J Med Sci.

2015;3(4):613-8.

ICTROMI 2019 - The 2nd International Conference on Tropical Medicine and Infectious Disease

Fang H, Ning DS, dan Liang XY, 2009. Studies on

Technology Optimization for Extracting Triterpenoid

Saponins from Picria felterrae by Multi-Target

Grading Method. Journal of Chinese Medicinal

Material. 32(12):1902-5.

Fu Y, Luo N, Klein RL, Garvey WT, 2005. Adiponectin

promotes adipocyte differentiation, insulin sensitivity,

and lipid accumulation. J. Lipid Res. 46;1369–79.

Huang Y, de Bruyne T, Apers S, Ma Y, Claeys M, van

den Berghe D, Pieters L, Vlietinck, A, 1998.

Complement-Inhibiting Cucurbitacin Glycosides from

Picria felterrae. Journal of Natural Products.

61(6):757-61.

Iannitti T, Graham A, Dolan S, 2015. Adiponectin-

mediated analgesia and anti-inflammatory effects in

the rat. PLoS One. 10(9):e0136819.

Kemenkes RI. Farmakope Herbal Indonesia, 2013. Ed.I

Suplemen II. Kemenkes RI Jakarta.106-7.

Kumari M and Tannins JS, 2012. An Antinutrient with

Positive Effect to Manage Diabetes Res. J. Recent Sci.

1(12):1-8.

Lindarto D, Machrina Y, Syafril S, Saragih A, 2019. The

Effect Of Puguntano (Curanga Fel-Terrae [Lour.])

Extract On Adiponectin Receptor (Adipor) In Rats

With Type 2 Diabetes Mellitus. Asian J Pharm Clin

Res, 12(2):551-3.

Lindarto D, Syafril S, Zein U, Saragih A, 2016. The

Effect Of Dhawalsan-1 (Curanga Fel-Terrae [Lour.])

Extract Versus Metformin On The Metabolic And

Inflammatory Characteristics Of Patients With Newly

Diagnosed Type 2 Diabetes Mellitus. Asian J Pharm

Clin Res. 9 Suppl 1:225-8.

Liu M, Xiang R, Wilk SA., Zhang N, Sloane

LB, Azarnoush K, et al, 2012. Fat-specific Dsb A-L

overexpression promotes adiponectin multimerization

and protects mice from diet-induced obesity and

insulin resistance. Diabetes. 61(11):2776-86.

Mao X, Kikani, CK, Riojas RA, Langlais P, Wang

L, Ramos FJ, et al, 2006. APPL1 binds to adiponectin

receptors and mediates adiponectin signaling and

function. Nat. Cell Biol. 8(5):516–23.

Syafril S, Lindarto D, Lelo A, Sembiring RJ, Manaf A,

Putra IB, Hasibuan PAZ, Mutiara E, 2019. The Effect

of Puguntano Leaf Extract (Curanga Fel Terrae

Merr.) on p38-MAPK Levels and Glut-4 Expression

in Type 2 Diabetic Rat Muscle. OA Maced J Med

Sci. 7(4):521-5.

Wang LS, Li SH, Zou JM, Guo YJ, Sun HD, 2006. Two

New Terpenoids from Picria feel-terrae. Journal of

Asian Natural Product Research. 8(6):491-4.

Xin X, Zhou L, Reyes CM. Liu F, Dong LQ, 2011.

APPL1 mediates adiponectin stimulated p38 MAPK

activation by scaffolding the TAK1-MKK3-p38

MAPK pathway. Am. J. Physiol. Endocrinol. Metab.

2011;300(1):E103–E10.

Yamauchi T, Kadowaki T, 2008. Physiological and

pathophysiological roles of adiponectin and

adiponectin receptors in the integrated regulation of

metabolic and cardiovascular diseases. Int J Obes

(Lond). 32 Suppl 7: S13-8.

Yamauchi T, Kamon J, Minokoshi Y, Ito Y, Waki

H, Uchida S, et al, 2002. Adiponectin stimulates

glucose utilization and fatty-acid oxidation by

activating AMP-activated protein kinase. Nat. Med.

8(11):1288-95.

Yamauchi T, Kamon J, Waki H., Terauchi Y, Kubota

N, Hara, et al, 2001. The fat-derived hormone

adiponectin reverses insulin resistance associated with

both lipoatrophy and obesity. Nat. Med. 7(8):941-6.

Yamauchi T, Nio Y, Maki T, Kobayashi M, Takazawa

T, Iwabu M, et al, 2007. Targeted disruption of

AdipoR1 and AdipoR2 causes abrogation of

adiponectin binding and metabolic actions. Nat. Med.

13(3):332-9.

Zhang M, Lv XY, Li J, Xu ZG, Chen L, 2008. The

Characterization of a high-fat diet and multiple low-

dose streptozotocin-induced type 2 diabetes rat model.

Exp Diabetes Res.1-9.

Zhou JM, Wang LS, Niu XM, Sun HD, Guo YJ, 2005.

Phenylethanoid Glycosides from Picria felterrae Lour.

Journal of Integrative Plant Biology. 47(5):632-6.

Correlation between Adiponectin Receptor (AdipoR) with Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Peroxisome

Proliferator-Activated Receptor Gamma (PPAR-), and p38-mitogen-activated protein kinases (MAPK) in Type 2 Diabetic Rats Treated with

Puguntano (Turanga feel-terrae Lour.) Leaves Extract