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://www.jofem.org

Original Article

Volume 14, Number 4, August 2024, pages 184-193

Evaluation Effect of Low-Intensity Pulsed Ultrasound on Blood Insulin Secretion due to Pancreatic Stimulation in Type 2 Diabetic Male Rats

Figures

Figure 1.
Figure 1. Experimental timeline. *At 35 mg/kg body weight. NDC: non-diabetic control; DC: diabetic control; DT + US: diabetic treated with ultrasound at intensity of 1 W/cm2 (DT + US1), diabetic treated with ultrasound at intensity of 1.5 W/cm2 (DT + US1.5); STZ: streptozotocin.
Figure 2.
Figure 2. Schematic of the sonication procedure for a diabetic rat under anesthesia. The probe ultrasound transducer was positioned transcutaneously over the abdomen, which was then shaved and covered with ultrasound coupling gel [14] (created with BioRender.com, by permission of use)..
Figure 3.
Figure 3. The graph of the biochemical analysis of the effects of ultrasound treatment on the serum levels of (a) insulin, (b) glucose, (c) glucagon, and (d) somatostatin. aP < 0.05. bP < 0.01. cP < 0.001 versus NDC. dP < 0.05. eP < 0.01. fP < 0.001. gP < 0.0001 versus DC. NDC: non-diabetic control; DC: diabetic control; DT + US: diabetic treated with ultrasound at intensity of 1 W/cm2 (DT + US1), diabetic treated with ultrasound at intensity of 1.5 W/cm2 (DT + US1.5).
Figure 4.
Figure 4. Comparison of (a) insulin and (b) glucose levels between treated groups (DT + US1 vs. DT + US1.5). There were no significant differences (P > 0.05) with increasing ultrasound intensity from 1 W/cm2 to 1.5 W/cm2 in terms of enhanced insulin secretion or reduced glucose levels. DT + US: diabetic treated with ultrasound at intensity of 1 W/cm2 (DT + US1), diabetic treated with ultrasound at intensity of 1.5 W/cm2 (DT + US1.5).
Figure 5.
Figure 5. Photomicrographs of H&E sections of rat pancreas, liver and spleen from NDC, DC, and DT+US (diabetic treated with ultrasound at intensity of 1 W/cm2 (DT + US1); diabetic treated with ultrasound at intensity of 1.5 W/cm2 (DT + US1.5). (a) NDC rat pancreas showing normal islets of Langerhans (arrow). (b) DC rat pancreas showing shrinkage of islets of Langerhans with degeneration and necrosis of components cells (arrow). (c) DT + US1 and (d) DT + US1.5 rat pancreas showing the islets of Langerhans maintain their circular shape, no cell lysis or damage is visible throughout the samples and tissue integrity is retained (arrows). (e) NDC rat liver, showing normal hepatocytes (arrow). (f) DC rat liver showing increased vacuolation in the cytoplasm of hepatocytes appeared as indistinct clear vacuoles (arrows). (g) DT + US1 and (h) DT + US1.5 rat liver, showing no gross visible damage, including bleeding, burns or discoloration (arrows) (i) NDC rat spleen showing the normal architecture of the spleen (arrows). (j) DC rat spleen showing splenic lesions, such as histological changes, atrophy, and splenocyte apoptosis (arrow). (k) DT + US1 and (l) DT + US1.5 rat spleen, showing an absence of overt tissue damage, such as burns or bleeding (arrows). Magnification: (a-d): × 40, scale bar: 20 µm; (e-h): × 20, scale bar: 50 µm; (i-l): × 4, scale bar: 100 µm. H&E: hematoxylin and eosin stain; NDC: non-diabetic control; DC: diabetic control; DT + US: diabetic treated with ultrasound.

Tables

Table 1. Changes in the Mean Temperature (ΔTmean) of the Pancreas After Ultrasound Exposure
 
Technique
ΔTmean in I = 0.5 W/cm2ΔTmean in I = 1 W/cm2ΔTmean in I = 1.5 W/cm2
A plane circular transducer (area: 1 cm2) was placed on the abdomen surface and exposed to the pulse (1:2 and 1:8), with intensities of 0.5, 1 and 1.5 W/cm2, frequency = 1 MHz; time = 15 min. ΔTmean was recorded by an IR camera and thermometer. Each value represents the mean ± SEM of three rats per group. SEM: standard error of mean.
Pulse 1:20.43 ± 0.07 °C0.51 ± 0.09 °C0.62 ± 0.12 °C
Pulse 1:80.24 ± 0.02 °C0.37 ± 0.04 °C0.40 ± 0.04 °C

 

Table 2. Effect of LIPUS Treatment on Levels of Insulin, Glucose, Glucagon, Somatostatin, HOMA-IR, HOMA-B, and QUICKI
 
Groups
NDCDCDT + US1DT + US1.5
Each value represents the mean ± SEM of 6 - 8 rats per group. aP < 0.05. bP < 0.01. cP < 0.001 versus NDC. dP < 0.05. eP < 0.01. fP < 0.001 versus DC. LIPUS: low-intensity pulsed ultrasound; HOMA-IR; homeostasis model assessment of insulin resistance; HOMA-B: homeostasis model assessment of beta-cell function; QUICKI: quantitative insulin sensitivity check index; NDC: non-diabetic control; DC: diabetic control; DT + US: diabetic treated with ultrasound at intensity of 1 W/cm2 (DT + US1), diabetic treated with ultrasound at intensity of 1.5 W/cm2 (DT + US1.5).
Insulin (pmol/L)17.98 ± 1.0412.52 ± 0.57a20.38 ± 1.06f22.50 ± 1.18f
Glucose (mg/dL)173.89 ± 10.84275.34 ± 2.78c152.40 ± 14.44f148.35 ± 21.32e
Glucagon (pg/mL)3.99 ± 0.245.22 ± 0.287.24 ± 0.52b, d7.62 ± 0.42c, e
Somatostatin (pg/mL)4.20 ± 0.243.99 ± 0.173.83 ± 0.343.54 ± 0.28
HOMA-IR1.31 ± 0.161.42 ± 0.061.28 ± 0.141.38 ± 0.22
HOMA-B10.02 ± 0.733.55 ± 0.19b16.90 ± 2.56e16.14 ± 2.43d
QUICKI0.370 ± 0.0060.363 ± 0.0020.372 ± 0.0070.378 ± 0.017