J Endocrinol Metab

Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc

Journal website https://jem.elmerpub.com

Original Article

Volume 15, Number 4, October 2025, pages 144-152

Role of Adiponectin in Modulating Insulin Resistance in Visceral Obesity-Associated Type 2 Diabetes Mellitus

Figure 1. Pathway illustrating the regulatory role of adiponectin via AMPK and PPAR-α signaling. Adiponectin binding to AdipoR1/AdipoR2 activates AMPK and PPAR-α, promoting glucose uptake in skeletal muscle, enhancing fatty acid oxidation and suppressing hepatic gluconeogenesis, thereby improving insulin sensitivity. AdipoR1: adiponectin receptor 1; AdipoR2: adiponectin receptor 2; AMPK: AMP-activated protein kinase; PPAR-α: peroxisome proliferator-activated receptor-alpha.

**Table 1.** Normality Assessment of Variables in Overweight and Obese Groups
Variable	Shapiro-Wilk P (overweight)	Normality (overweight)	Shapiro-Wilk P (obese)	Normality (obese)
P < 0.05 was considered as significant. BMI: body mass index; FPG: fasting plasma glucose; HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment for insulin resistance; LDL: low-density lipoprotein; PPBG: postprandial blood glucose; TC: total cholesterol; TG: triglycerides; WC: waist circumference.
Age	0.010	Non-normal	0.001	Non-normal
Height	0.190	Normal	0.153	Normal
Weight (kg)	0.016	Non-normal	0.372	Normal
WC (cm)	0.001	Non-normal	0.001	Non-normal
BMI (kg/m²)	0.040	Non-normal	0.028	Non-normal
FPG (mmol/L)	0.046	Non-normal	0.395	Normal
PPBG (mmol/L)	0.385	Normal	0.027	Non-normal
HbA1c (%)	0.532	Normal	0.019	Non-normal
Insulin (µIU/mL)	0.019	Non-normal	0.096	Normal
HOMA-IR	0.001	Non-normal	0.001	Non-normal
Adiponectin (µg/mL)	0.001	Non-normal	0.001	Non-normal
TC (mmol/L)	0.001	Non-normal	0.001	Non-normal
TG (mmol/L)	0.005	Non-normal	0.261	Normal
HDL (mmol/L)	0.001	Non-normal	0.001	Non-normal
LDL (mmol/L)	0.001	Non-normal	0.001	Non-normal

Table 1. Normality Assessment of Variables in Overweight and Obese Groups

Variable

Shapiro-Wilk P (overweight)

Normality (overweight)

Shapiro-Wilk P (obese)

Normality (obese)

P < 0.05 was considered as significant. BMI: body mass index; FPG: fasting plasma glucose; HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment for insulin resistance; LDL: low-density lipoprotein; PPBG: postprandial blood glucose; TC: total cholesterol; TG: triglycerides; WC: waist circumference.

Age

0.010

Non-normal

0.001

Non-normal

Height

0.190

Normal

0.153

Normal

Weight (kg)

0.016

Non-normal

0.372

Normal

WC (cm)

0.001

Non-normal

0.001

Non-normal

BMI (kg/m²)

0.040

Non-normal

0.028

Non-normal

FPG (mmol/L)

0.046

Non-normal

0.395

Normal

PPBG (mmol/L)

0.385

Normal

0.027

Non-normal

HbA1c (%)

0.532

Normal

0.019

Non-normal

Insulin (µIU/mL)

0.019

Non-normal

0.096

Normal

HOMA-IR

0.001

Non-normal

0.001

Non-normal

Adiponectin (µg/mL)

0.001

Non-normal

0.001

Non-normal

TC (mmol/L)

0.001

Non-normal

0.001

Non-normal

TG (mmol/L)

0.005

Non-normal

0.261

Normal

HDL (mmol/L)

0.001

Non-normal

0.001

Non-normal

LDL (mmol/L)

0.001

Non-normal

0.001

Non-normal

**Table 2.** Anthropometric and Biochemical Parameters in Overweight and Obese Participants
Variable	Overweight (mean ± SD/median (IQR))	Obese (mean ± SD/median (IQR))	Test statistic	P-value
Mean ± SD is used for normally distributed data, and median (IQR) is used for non-normally distributed variables. P < 0.05 was considered as significant. BMI: body mass index; FPG: fasting plasma glucose; HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment for insulin resistance; LDL: low-density lipoprotein; PPBG: postprandial blood glucose; TC: total cholesterol; TG: triglycerides; WC: waist circumference.
Height (cm)	168.42 ± 8.24	166.86 ± 8.82	t = 1.079	0.283
Weight (kg)	77.1 (71.2 - 81.6)	90.0 (83.0-96.4)	U = 780.5	< 0.001
WC (cm)	97.0 (94.0 - 97.0)	101.3 (97.5 - 105.6)	U = 1,343.5	< 0.001
BMI (kg/m²)	27.3 (26.1 - 28.2)	32.4 (31.2 - 33.0)	U = 0.0	< 0.001
FPG (mmol/L)	13.6 (12.7 - 15.1)	13.9 (13.1 - 14.4)	U = 2,061.0	0.126
PPBG (mmol/L)	17.1 (15.9 - 19.5)	17.7 (16.4 - 20.1)	U = 2,153.0	0.254
HbA1c (%)	9.0 (8.3 - 10.2)	9.3 (8.6 - 9.9)	U = 2,127.0	0.211
Insulin (µIU/mL)	6.6 (6.2 - 7.0)	6.5 (6.2 - 6.9)	U = 1,922.5	0.035
HOMA-IR	4.0 (4.0 - 4.0)	4.0 (4.0 - 4.0)	U = 2,415.0	0.958
Adiponectin (µg/mL)	11.3 (10.7 - 12.0)	11.3 (10.5 - 11.6)	U = 1,891.5	0.016
TC (mmol/L)	5.3 (5.2 - 5.4)	5.3 (5.2 - 5.4)	U = 2,079.5	0.125
TG (mmol/L)	3.2 (3.0 - 3.4)	3.3 (3.2 - 3.5)	U = 2,061.5	0.124
HDL (mmol/L)	1.1 (1.0 - 1.1)	1.1 (1.0 - 1.1)	U = 1,922.5	0.015
LDL (mmol/L)	2.7 (2.7 - 2.8)	2.8 (2.7 - 2.8)	U = 2,205.0	0.286

Table 2. Anthropometric and Biochemical Parameters in Overweight and Obese Participants

Variable

Overweight (mean ± SD/median (IQR))

Obese (mean ± SD/median (IQR))

Test statistic

P-value

Mean ± SD is used for normally distributed data, and median (IQR) is used for non-normally distributed variables. P < 0.05 was considered as significant. BMI: body mass index; FPG: fasting plasma glucose; HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment for insulin resistance; LDL: low-density lipoprotein; PPBG: postprandial blood glucose; TC: total cholesterol; TG: triglycerides; WC: waist circumference.

Height (cm)

168.42 ± 8.24

166.86 ± 8.82

t = 1.079

0.283

Weight (kg)

77.1 (71.2 - 81.6)

90.0 (83.0-96.4)

U = 780.5

< 0.001

WC (cm)

97.0 (94.0 - 97.0)

101.3 (97.5 - 105.6)

U = 1,343.5

< 0.001

BMI (kg/m²)

27.3 (26.1 - 28.2)

32.4 (31.2 - 33.0)

U = 0.0

< 0.001

FPG (mmol/L)

13.6 (12.7 - 15.1)

13.9 (13.1 - 14.4)

U = 2,061.0

0.126

PPBG (mmol/L)

17.1 (15.9 - 19.5)

17.7 (16.4 - 20.1)

U = 2,153.0

0.254

HbA1c (%)

9.0 (8.3 - 10.2)

9.3 (8.6 - 9.9)

U = 2,127.0

0.211

Insulin (µIU/mL)

6.6 (6.2 - 7.0)

6.5 (6.2 - 6.9)

U = 1,922.5

0.035

HOMA-IR

4.0 (4.0 - 4.0)

U = 2,415.0

0.958

Adiponectin (µg/mL)

11.3 (10.7 - 12.0)

11.3 (10.5 - 11.6)

U = 1,891.5

0.016

TC (mmol/L)

5.3 (5.2 - 5.4)

U = 2,079.5

0.125

TG (mmol/L)

3.2 (3.0 - 3.4)

3.3 (3.2 - 3.5)

U = 2,061.5

0.124

HDL (mmol/L)

1.1 (1.0 - 1.1)

U = 1,922.5

0.015

LDL (mmol/L)

2.7 (2.7 - 2.8)

2.8 (2.7 - 2.8)

U = 2,205.0

0.286

**Table 3.** Correlation of Adiponectin With Anthropometric and Biochemical Parameters
Variable	All cases (ρ)	P-value	Overweight (ρ)	Overweight (P-value)	Obese (ρ)	Obese (P-value)
Data are represented as Spearman rank correlation coefficient (ρ). Correlation is significant at 0.05 level (two-tailed). *Correlation is significant at 0.01 level (two-tailed). BMI: body mass index; FPG: fasting plasma glucose; HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment for insulin resistance; LDL: low-density lipoprotein; PPBG: postprandial blood glucose; TC: total cholesterol; TG: triglycerides; WC: waist circumference.
WC (cm)	-0.230**	0.006	-0.35*	0.025	-0.45*	0.008
BMI (kg/m²)	-0.173*	0.041	-0.28*	0.041	-0.38*	0.015
Insulin (µIU/mL)	0.750**	< 0.001	0.749**	< 0.001	0.763**	< 0.001
HOMA-IR	-0.45**	< 0.001	-0.45*	0.010	-0.61**	< 0.001
FPG (mmol/L)	-0.785**	< 0.001	-0.796**	< 0.001	-0.772**	< 0.001
PPBG (mmol/L)	-0.648**	< 0.001	-0.704**	< 0.001	-0.559**	< 0.001
HbA1c (%)	-0.640**	< 0.001	-0.675**	< 0.001	-0.577**	< 0.001
TC (mmol/L)	-0.738**	< 0.001	-0.795**	< 0.001	-0.666**	< 0.001
TG (mmol/L)	-0.792**	< 0.001	-0.807**	< 0.001	-0.777**	< 0.001
HDL (mmol/L)	0.918**	< 0.001	0.923**	< 0.001	0.915**	< 0.001
LDL (mmol/L)	-0.552**	< 0.001	-0.565**	< 0.001	-0.545**	< 0.001

Table 3. Correlation of Adiponectin With Anthropometric and Biochemical Parameters

Variable

All cases (ρ)

P-value

Overweight (ρ)

Overweight (P-value)

Obese (ρ)

Obese (P-value)

Data are represented as Spearman rank correlation coefficient (ρ). *Correlation is significant at 0.05 level (two-tailed). **Correlation is significant at 0.01 level (two-tailed). BMI: body mass index; FPG: fasting plasma glucose; HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; HOMA-IR: homeostatic model assessment for insulin resistance; LDL: low-density lipoprotein; PPBG: postprandial blood glucose; TC: total cholesterol; TG: triglycerides; WC: waist circumference.

WC (cm)

-0.230**

0.006

-0.35*

0.025

-0.45*

0.008

BMI (kg/m²)

-0.173*

0.041

-0.28*

0.041

-0.38*

0.015

Insulin (µIU/mL)

0.750**

< 0.001

0.749**

< 0.001

0.763**

< 0.001

HOMA-IR

-0.45**

< 0.001

-0.45*

0.010

-0.61**

< 0.001

FPG (mmol/L)

-0.785**

< 0.001

-0.796**

< 0.001

-0.772**

< 0.001

PPBG (mmol/L)

-0.648**

< 0.001

-0.704**

< 0.001

-0.559**

< 0.001

HbA1c (%)

-0.640**

< 0.001

-0.675**

< 0.001

-0.577**

< 0.001

TC (mmol/L)

-0.738**

< 0.001

-0.795**

< 0.001

-0.666**

< 0.001

TG (mmol/L)

-0.792**

< 0.001

-0.807**

< 0.001

-0.777**

< 0.001

HDL (mmol/L)

0.918**

< 0.001

0.923**

< 0.001

0.915**

< 0.001

LDL (mmol/L)

-0.552**

< 0.001

-0.565**

< 0.001

-0.545**

< 0.001