Concurrent Chemoradiotherapy-Driven Cell Plasticity by miR-200 Family Implicates the Therapeutic Response of Esophageal Squamous Cell Carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common and fatal malignancy with an increasing incidence worldwide. Over the past decade, concurrent chemoradiotherapy (CCRT) with or without surgery is an emerging therapeutic approach for locally advanced ESCC. Unfortunately, many patients exhibit poor response or develop acquired resistance to CCRT. Once resistance occurs, the overall survival rate drops down rapidly and without proper further treatment options, poses a critical clinical challenge for ESCC therapy. Here, we utilized lab-created CCRT-resistant cells as a preclinical study model to investigate the association of chemoradioresistantresistance with miRNA-mediated cell plasticity alteration, and to determine whether reversing EMT status can re-sensitize refractory cancer cells to CCRT response. During the CCRT treatment course, refractory cancer cells adopted the conversion of epithelial to mesenchymal phenotype; additionally, miR-200 family members were found significantly down-regulated in CCRT resistance cells by miRNA microarray screening. Down-regulated miR-200 family in CCRT resistance cells suppressed E-cadherin expression through snail and slug, and accompany with an increase in N-cadherin. Rescuing expressions of miR-200 family members in CCRT resistance cells, particularly in miR-200b and miR-200c, could convert cells to epithelial phenotype by increasing E-cadherin expression and sensitize cells to CCRT treatment. Conversely, the suppression of miR-200b and miR-200c in ESCC cells attenuated E-cadherin, and that converted cells to mesenchymal type by elevating N-cadherin expression, and impaired cell sensitivity to CCRT treatment. Moreover, the results of ESCC specimens staining established the clinical relevance that higher N-cadherin expression levels associate with the poor CCRT response outcome in ESCC patients. Conclusively, miR-200b and miR-200c can modulate the conversion of epithelial-mesenchymal phenotype in ESCC, and thereby altering the response of cells to CCRT treatment. Targeting epithelial-mesenchymal conversion in acquired CCRT resistance may be a potential therapeutic option for ESCC patients.

Factors Associated with Postoperative Rehospitalization in Patients with Cervical Disc Herniation.

Cervical disc herniation (CDH) is a prevalent disease because of the poor living habits of and great pressure in modern society. Patients experience hand numbness, neck stiffness, soreness, and weakness due to neck nerve root compression, which leads to a gradual increase of neurosurgery outpatients. Although poor posture by the overuse of computers is possibly the origin of CDH, analysis of related factors causing the rehospitalization for CDH patients after surgery in Taiwan is not commonly reported. Thus, the present study focused on the demographics and surgery-related treatment on the relevance of rehospitalization for CDH patients after surgery. The design of the study was retrospective, and we collected data by medical record review, which was derived from the inpatient surgery data of patients at a medical center in southern Taiwan. The study lasted two years from 1 January 2017 to 31 December 2018, and a total of 248 patients underwent surgery for intervertebral disc protrusion in the neck. The retrospective study adopted narrative statistics, the chi-squared test, and binary logistic regression analysis to identify factors affecting postoperative rehospitalization. Among 248 postoperative patients with intervertebral disc protrusion, 178 underwent cervical fusion surgery, and 32 were rehospitalized after surgery for one-year follow up, accounting for an overall prevalence rate of 12.9%. There were no significant differences in sex, age, occupation, hypertension, anterior cervical discectomy and fusion, artificial disc replacement, hybrid surgery, and postoperative cervical coil use (p > 0.05). The results of binary logistic regression analysis showed statistically significant differences in abnormal body mass index (p = 0.0187, 95% CI = 1.238-10.499), diabetes (p = 0.0137, 95% CI = 1.288-9.224) and cervical vertebral surgery hospital days (p = 0.0004, 95% CI = 1.028-1.102), predicting the outcome of rehospitalization for CDH patients after surgery. The above results showed that abnormal body mass index, diabetes, and cervical vertebral surgery hospitalization days impacted rehospitalization in CDH patients after surgery. Thus, to prevent diabetes, weight control must be monitored, and maintaining correct posture can reduce CDH and decrease the rate of rehospitalization after surgery, which provides a critical reference for hospital managers and clinical staff.

Alteration of loperamide-induced prostate relaxation in high-fat diet-fed rats.

OBJECTIVE: To investigate the change of loperamide-induced prostate relaxation in rats fed with high-fat diet (HFD). MATERIALS AND METHODS: Adult male Wistar rats were divided into 2 groups: (1) control rats fed with normal chow and (2) rats fed with HFD for 6 months. The prostate was removed for histology study. Isolated prostate strips were hung in organ bath and precontracted with 1 µmol/L phenylephrine or 50 mmol/L KCl. The relaxation responses to loperamide 0.1 to 10 µmol/L were recorded. Western blotting analyses were performed for prostate µ-opioid receptors (MOR) and ATP-sensitive potassium (K(ATP)) channel proteins: sulfonylurea receptor (SUR) and inwardly rectifying potassium channel (Kir) 6.2 subunits. RESULTS: Body weight, prostate weight, plasma levels of glucose, insulin, triglyceride, and cholesterol, as well as systolic blood pressure, were significantly increased in the HFD rats. Histology showed prostatic hyperplasia in the HFD rat prostate. Prostatic relaxation induced by loperamide was markedly reduced in HFD when compared to the control. Protein expressions of MOR, SUR, and Kir 6.2 were decreased in HFD-fed rats. CONCLUSION: Loperamide-induced prostate relaxation is decreased in HFD rats due to reduced MOR and K(ATP) channel expressions.

Silymarin induces insulin resistance through an increase of phosphatase and tensin homolog in Wistar rats.

BACKGROUND AND AIMS: Phosphatase and tensin homolog (PTEN) is a phosphoinositide phosphatase that regulates crucial cellular functions, including insulin signaling, lipid and glucose metabolism, as well as survival and apoptosis. Silymarin is the active ingredient in milk thistle and exerts numerous effects through the activation of PTEN. However, the effect of silymarin on the development of insulin resistance remains unknown. METHODS: Wistar rats fed fructose-rich chow or normal chow were administered oral silymarin to identify the development of insulin resistance using the homeostasis model assessment of insulin resistance and hyperinsulinemic- euglycemic clamping. Changes in PTEN expression in skeletal muscle and liver were compared using western blotting analysis. Further investigation was performed in L6 cells to check the expression of PTEN and insulin-related signals. PTEN deletion in L6 cells was achieved by small interfering ribonucleic acid transfection. RESULTS: Oral administration of silymarin at a dose of 200 mg/kg once daily induced insulin resistance in normal rats and enhanced insulin resistance in fructose-rich chow-fed rats. An increase of PTEN expression was observed in the skeletal muscle and liver of rats with insulin resistance. A decrease in the phosphorylation of Akt in L6 myotube cells, which was maintained in a high-glucose condition, was also observed. Treatment with silymarin aggravated high-glucose-induced insulin resistance. Deletion of PTEN in L6 cells reversed silymarin-induced impaired insulin signaling and glucose uptake. CONCLUSIONS: Silymarin has the ability to disrupt insulin signaling through increased PTEN expression. Therefore, silymarin should be used carefully in type-2 diabetic patients.

Urinary Bladder Relaxation through Activation of Imidazoline Receptors Induced by Agmatine is Increased in Diabetic Rats.

OBJECTIVES: The effect of agmatine on bladder contractility and the diabetes-induced alteration of this action were studied in the rat. METHODS: Bladder strips were isolated from 9-week-old streptozotocin (STZ)-diabetic rats and control Wistar rats. Strips were hung in an organ bath for measurement of isometric tension and pre-contracted with either 1 µmol/L acetylcholine (ACh) or 50 mmol/L KCl. Dose-dependent relaxation of the bladder strips was studied by cumulative administration of agmatine 1-100 µmol/L into the organ bath. Effects of specific imidazoline receptor (IR) antagonists on the agmatine-induced relaxation were studied. Western blotting analysis was used to measure bladder IR, sulphonylurea receptor (SUR) and inwardly rectifying K(+) channel subunit 6.2 (Kir 6.2) protein levels. RESULTS: Agmatine reduced ACh and KCl pre-contracted bladder strip tension in a dose-dependent fashion. Relaxation was significantly increased in STZ-diabetic rats. The relaxation was inhibited by BU224, a selective I2 IR antagonist; but not by efaroxan (I1 IR antagonist) or KU14R (I3 IR antagonist). Moreover, the agmatine-induced relaxation was attenuated by glibenclamide (inhibitor of KATP channel) and H-89 (inhibitor of protein kinase A), but enhanced by 3-isobutyl-1-methylxanthine (IBMX, inhibitor of cyclic AMP phosphodiesterase). Western blotting showed increased expression of bladder IR but not SUR or Kir 6.2 in the STZ-diabetic rat. CONCLUSION: Agmatine causes rat bladder relaxation by activation of the I2 IR, which opens KATP channels through the cyclic AMP/protein kinase A pathway. Agmatine-induced bladder relaxation in STZ-diabetic rats is increased due to a higher expression of IR.

Antihyperglycemic action of sinapic acid in diabetic rats.

Sinapic acid is a hydroxycinnamic acid contained in plants. In an attempt to know the hyperglycemic effect of sinapic acid, this study applied streptozotocin (STZ) to induce type 1-like diabetic rats and fed fructose-rich chow to induce type 2-like diabetic rats. Sinapic acid dose-dependently reduced the hyperglycemia of STZ-diabetic rats (9.8 ± 1.8%, 11.6 ± 0.7%, and 19.4 ± 3.2% at 5 mg/kg, 10 mg/kg, and 25 mg/kg, respectively). Also, sinapic acid attenuated the postprandial plasma glucose without changing plasma insulin in rats. Repeated treatment of sinapic acid increased the gene expression of GLUT4 in soleus muscle of STZ-diabetic rats. Moreover, sinapic acid enhanced glucose uptake into isolated soleus muscle and L6 cells (337.0 ± 29.6%). Inhibition of phospholipase C (PLC) using U73122 (1.00 ± 0.02 µg/mg protein) or protein kinase C (PKC) using chelerythrine (0.97 ± 0.02 µg/mg protein) attenuated the sinapic acid-stimulated glucose uptake (1.63 ± 0.02 µg/mg protein) in L6 cells. Otherwise, the reduced glucose infusion rate (GIR) in fructose-rich chow-fed rats was also raised by sinapic acid. Our results suggest that sinapic acid ameliorates hyperglycemia through PLC-PKC signals to enhance the glucose utilization in diabetic rats.

Decrease of Plasma Glucose by Hibiscus taiwanensis in Type-1-Like Diabetic Rats.

Hibiscus taiwanensis (Malvaceae) is widely used as an alternative herb to treat disorders in Taiwan. In the present study, it is used to screen the effect on diabetic hyperglycemia in streptozotocin-induced diabetic rats (STZ-diabetic rats). The extract of Hibiscus taiwanensis showed a significant plasma glucose-lowering action in STZ-diabetic rats. Stems of Hibiscus taiwanensis are more effective than other parts to decrease the plasma glucose in a dose-dependent manner. Oral administration of Hibiscus taiwanensis three times daily for 3 days into STZ-diabetic rats increased the sensitivity to exogenous insulin showing an increase in insulin sensitivity. Moreover, similar repeated administration of Hibiscus taiwanensis for 3 days in STZ-diabetic rats produced a marked reduction of phosphoenolpyruvate carboxykinase (PEPCK) expression in liver and an increased expression of glucose transporter subtype 4 (GLUT 4) in skeletal muscle. Taken together, our results suggest that Hibiscus taiwanensis has the ability to lower plasma glucose through an increase in glucose utilization via elevation of skeletal GLUT 4 and decrease of hepatic PEPCK in STZ-diabetic rats.

Decrease of Obesity by Allantoin via Imidazoline I 1 -Receptor Activation in High Fat Diet-Fed Mice.

The activation of the imidazoline I1-receptor (I1R) is known to regulate appetite. Allantoin, an active ingredient in the yam, has been reported to improve lipid metabolism in high fat diet- (HFD-)fed mice. However, the effect of allantoin on obesity remains unclear. In the present study, we investigated the effects of allantoin on HFD-induced obesity. The chronic administration of allantoin to HFD-fed mice for 8 weeks significantly decreased their body weight, and this effect was reversed by efaroxan at a dose sufficient to block I1R. The epididymal white adipose tissue (eWAT) cell size and weight in HFD-fed mice were also decreased by allantoin via the activation of I1R. In addition, allantoin significantly decreased the energy intake of HFD-fed mice, and this reduction was associated with a decrease in the NPY levels in the brain. However, no inhibitory effect of allantoin on energy intake was observed in db/db mice. Moreover, allantoin lowered HFD-induced hyperleptinemia, and this activity was abolished by I1R blockade with efaroxan. Taken together, these data suggest that allantoin can ameliorate energy intake and eWAT accumulation by activating I1R to improve HFD-induced obesity.