This study was undertaken to characterize the insulin resistance and the mechanism thereof caused by chronic hyperinsulinemia produced in dogs by surgically diverting the veins of the pancreas from the portal vein to the vena cava. Pancreatic venous diversion (PVD, n = 8) caused a sustained increase in arterial insulin and decrease in portal insulin concentration compared with the control group (n = 6). Hyperinsulinemic euglycemic clamps were conducted 4 wk after surgery. The increase in the glucose disposal rate (GDR) was significantly less in the PVD group (39.0+/-5.0 vs. 27.9+/-3.2 micromol/kg/min, P < 0.01) compared with the control group, but the suppression of hepatic glucose production by insulin was similar for both groups. Muscle insulin receptor tyrosine kinase activity (IR-TKA) increased from 6.2+/-0.4 to 20.3+/-2.7 in the control group, but from 5.8+/-0.5 to only 12.7+/-1.7 fmol P/fmol IR in the PVD group (P < 0.01). With respect to the periphery, the time to half-maximum response (t1/2a) for arterial insulin was the same for both groups, whereas the t1/2a for lymph insulin (30+/-3 vs. 40+/-4 min, P < 0.05) and GDR (29+/-3 vs. 66+/-10 min, P < 0.01) were greater for the PVD group. Chronic hyperinsulinemia led to marked peripheral insulin resistance characterized by decreased insulin-stimulated GDR, and impaired activation of GDR kinetics due, in part, to reduced IR-TKA. Transendothelial insulin transport was impeded and was responsible for one third of the kinetic defect in insulin-resistant animals, while slower intracellular mechanisms of GDR were responsible for the remaining two thirds.

Objectives. Salvia fruticosa Mill. (S. fruticosa) is widely used in folk medicine. Accordingly, the present study was designed to evaluate the antioxidant and anti-inflammatory activities of S. fruticosa, and to determine the phenolic constituents of its extracts. Methods. The antioxidant activity was determined using 2,2-diphenylpicrylhydrazyl assay. Total phenolic contents were estimated using Folin-Ciocalteu reagent, and high-performance liquid chromatography was performed to identify phenolic constituents. To evaluate the anti-inflammatory activity, carrageenan-induced mouse paw edema was determined plethysmographically. Key Findings. Different plant extracts demonstrated strong radical scavenging activity, where the ethyl acetate extract had the highest value in the roots and the lowest in the aerial parts. This antioxidant activity was correlated to the total phenolic content of different extracts, where rutin and luteolin were the most abundant constituents. Interestingly, both the roots and aerial parts revealed a significant anti-inflammatory activity comparable to diclofenac. Conclusions. This study is the first to demonstrate pharmacologic evidence of the potential anti-inflammatory activity of S. fruticosa. This activity may partly be due to the radical scavenging effects of its polyphenolic contents. These findings warrant the popular use of the East Mediterranean sage and highlight the potential of its active constituents in the development of new anti-inflammatory drugs.

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Rheum ribes L., known as Syrian rhubarb, is used in traditional Lebanese folk medicine for the treatment of diabetes. The present study aims to investigate the activities of R. ribes aqueous extract for glucose homeostasis, in vivo antioxidant and diabetic neuropathy protection in mice. The acute and the subacute effects of various doses of R. ribes on blood glucose and in vivo antioxidant activity utilizing serum catalase level (CAT) were studied in alloxan-diabetic mice. The high doses significantly lowered glucose level and increased serum CAT in alloxan-diabetic mice. Pretreatment with the extract prior to alloxination, protected the mice from acquiring diabetes and diabetic neuropathy. Treatment with the extract for 8 weeks alleviated hyperalgesia in diabetic mice. Our findings provide clinicians with promising drugs intended for the management of the symptoms of diabetic complications. The protective activity of R. ribes against acquiring diabetes and diabetic neuropathy might pave the way for preparing a prophylactic treatment for diabetes risk groups.

Introduction:The alarming increase in bacterial strains resistant to existing antimicrobial agents has demanded alternative strategies. Medicinal plants are now considered as an alternative treatment because of their secure choice in several diseases. Among them, Nigella sativa is a promising traditional herb having rich medical background. The aim of the study is to perform phytochemical analysis of Nigella sativa L. Utilizing Gas chromatographic-mass spectrometric (GC/MS) exploring its antioxidant and antibacterial activity against multidrug resistant (MDR) gram-positive and gram-negative bacteria. Methods: Total phenolic, tannin, and flavonoid content of N. sativa seed extracts and its commercially available oil were determined. Their radical scavenging activity using DPPH was also tested. The antibacterial activity of N. sativa seed extracts and its oil against MDR gram-positive and gram-negative bacterial strains was studied using disc diffusion test and the biofilm formation assay. GC-MS studies were also performed. Results: Among the different preparations used, N. sativa oil showed the highest antioxidant and antibacterial activity against highly resistant gram-positive bacteria with the greatest suppression of biofilm formation, which was attributed to its high bioactive contents. Conclusion: This study indicates that N. sativa extracts and its oils can be used as natural antibacterial agents to treat infections caused by multidrug resistant bacteria.