Histomorphometry Changes and Decreased Reactivity to Angiotensin II in the Ileum and Colon of Streptozotocin-Induced Diabetic Rats

Abstract

Diabetes mellitus (DM) is a chronic progressive metabolic disorder associated with several gastrointestinal complications, affecting up to 75% of patients. Knowing that Angiotensin II (AngII) also regulates intestinal contraction, we decided to evaluate changes in ileum and colon histomorphometry and AngII reactivity in a rat model of DM. Streptozotocin (STZ, 55 mg/kg) was administered to induce DM to 24 adult male Wistar rats. Diabetic rats displayed all the characteristic signs of type 1 DM (T1DM) and fecal excretion increased about 4-fold over 14 days, while the excretion of controls remained unaltered. Compared to controls, diabetic ileum and colon presented an increase in both macroscopic (length, perimeter and weight) and microscopic (muscular wall thickness) parameters. Functionally, AngII-induced smooth muscle contraction was lower in diabetic rats, except in the distal colon. These differences in the contractile response to AngII may result from an imbalance between AngII type 1 (antagonized by candesartan, 10 nM) and type 2 receptors activation (antagonized by PD123319, 100 nM). Taken together, these results indicate that an early and refined STZ-induced T1DM rat model already shows structural remodelling of the gut wall and decreased contractile response to AngII, findings that may help to explain diabetic dysmotility.

Small intestine histologic neuronal features of type-2 diabetes mellitus rats treated with ethanolic extract red betel leaf (Piper crocatum) nanoparticle (EERbLNp)

“…Thus, the neuron alteration in the muscular plexus may explain the sensory-motor function changes. Intestinal function alteration in the strepto zotocin-induced diabetic rat is also associated with a declined level of Angiotensin II, which controls small intestine contraction [4]. Necrotic features of neurons in the Meissner plexus were lesser than degenerated form in the T2DM group (Figure 1-3: F) and may be addressed to neuro degenerative complications in the diabetic patient [24].…”

“…Histological alteration in the Auerbach plexus correlates to their function in controlling muscular contraction and intestine motility. It also may be associated with most cases in T2DM patients that manifest, abdominal pain, bloating, constipation, or diarrhea [4,5]. Damaged ENS by prolonged hyperglicemia and oxidative stress in T2DM denotes diabetes-associatedintestinal motility alteration [6].…”

“…Beta cell dysfunction and insulin resistance lead to persistent hyperglycemia, which characterizes T2DM [3]. Gastrointestinal motility disorder is a common complication in around 75% of cases found in each segment of the digestive system and manifests as nausea, vomitus, abdominal pain, bloating, constipation, or diarrhea [4,5]. However, information about the intestine histological features of T2DM patients is still lacking.…”

Effect of Tangshen formula on the remodeling of small intestine and colon in Zucker diabetic fatty rats

“…It has been demonstrated that the histomorphological and biomechanical remodeling of gastrointestinal tract including small intestine and colon occurred during the development of diabetes in several diabetic animals [ 2 ]. In STZ-induced diabetic rat models, both small intestine [ 15 , [18] , [19] , [20] , 36 ] and colon [ 14 , 20 , 21 , 36 ] expressed as increasing in wet weight per unit length, total wall and layered wall thickness, and wall area. Collagen increasing in colonic mucosa has been reported [ 37 ].…”

Icariin Treatment Rescues Diabetes Induced Bone Loss via Scavenging ROS and Activating Primary Cilia/Gli2/Osteocalcin Signaling Pathway

“…SD rats aged 8 weeks were purchased from experimental Animal Center of Chongqing Medical University. The streptozotocin had toxic effects on pancreatic islet β-cells specially, causing almost all pancreatic β-cell necrosis [ 36 ]. Then STZ was dissolved into a sodium citrate buffer (50 mM, pH = 4.5) at a final concentration of 100 mg/mL.…”