AIMTo study the stability of insulin-loaded polybutylcyanoacrylate nanoparticles (IPN) in an oily medium (soybean oil containing 0.5% (v/v) Tween-20 and 5% (v/v) Vitamin E) along with the hypoglycemic effect following their oral administration to streptozotocin (STZ) induced diabetic rats.

METHODSThe stability of IPN in the process was appraised by measurement of the amount of undegraded insulin associated to nanoparticles, the average size and the span of IPN, as well as the release of insulin from IPN. IPN in an aqueous medium (containing 0.5% (v/v) Tween-20) at pH 2.0 was also investigated as control.

RESULTSThe study showed that IPN in the oily medium was more stable than that in the aqueous medium over one year of storage in the dark at (25 +/- 2) degrees C and the in vitro stability of IPN in the oily medium against degradation by proteolytic enzymes was much better than that in the aqueous medium. The apparent bioavailability of an oral administration of IPN (50 u x kg(-1)) in the oily medium versus an (sc) injection of insulin (2 u x kg(-1)) was 22.4%, much higher than that of IPN in the aqueous medium (15.5%), based on decreased areas above curve (AAC) determination for the blood glucose depression from time zero to 144 h of a single oral administration of IPN to STZ-diabetic rats.

CONCLUSIONIPN in soybean oil containing Tween-20 (0.5% v/v) and Vitamin E (5% v/v) could be considered as an effective and stable delivery system for oral insulin.

Administration, Oral ; Animals ; Biological Availability ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; metabolism ; Drug Carriers ; Drug Delivery Systems ; Drug Stability ; Enbucrilate ; Hypoglycemic Agents ; administration & dosage ; pharmacokinetics ; pharmacology ; Insulin ; administration & dosage ; pharmacokinetics ; pharmacology ; Male ; Nanostructures ; Particle Size ; Polymers ; Rats ; Rats, Wistar ; Soybean Oil

The normal function of vascular endothelial cells is an important foundation for maintaining vascular permeability， restricting inflammatory activities of the vascular wall， and balancing the coagulation and fibrinolytic system. Endothelial dysfunction caused by persistent damage from pathological factors is considered as an early and prominent event of diabetic macroangiopathy. In traditional Chinese medicine， the classical theory of "restraining excessiveness to acquire harmony" was originally a condensed generalization of the rule of generation， restriction， replacement and evolution in the natural world， revealing the internal regulation mechanism of the stable operation of things. Then it gradually evolved into an important rule to explain the physiological phenomena and pathological mechanism of human body and guide the treatment. Corresponding to the nature， the body homeostasis also requires to achieve a state of strong viscera function and inexhaustible Qi and blood generation under the rule of restriction and generation. The pathogenesis of diabetic macroangiopathy is the process of "the predominant one failing to restrict and the hyperactive one becoming harmful". The loss of restriction and generation of the five organs leads to powerless Qi transformation and， as a result， the Qi， blood and body fluid cannot be dispersed. Therefore， the Qi， blood and body fluid turn into phlegm and blood stasis， such as glucose and lipid metabolism disorder， oxidative stress， inflammatory response and high blood viscosity， and finally block the veins. Excessive phlegm and blood stasis cannot be resolved， instead they become harmful and invade the blood vessel， causing endothelial dysfunction and further resulting in diabetic macroangiopathy. Under the guidance of the theory of "restraining excessiveness to acquire harmony"， the method of "harmonizing viscera， eliminating pathogen and removing turbidity" can effectively regulate the function of vascular endothelial cells， thus playing a positive role in preventing and treating diabetic macroangiopathy. The mechanism may be related to reducing oxidative stress， inhibiting inflammation， limiting vascular smooth muscle proliferation， and reducing platelet adhesion.

Aim To explore the effeets of Salvianolie aeirl A (SAA) on platelet recruitment, activation and neutrophils in heart of myocardial infarction ( Ml ) mice.Methods C57BL/6 mice were randomly divid¬ed into: Sham operation group.Ml model group, SAA (5, 10 mg • kg 1 ) group, tirofiban (Tirofiban, 0.87 mg • kg ' ) group, using tail vein injection for 3 d.Echocardiography and HE staining were used to detect mouse heart function and infarct area; 1HC, FCS, ELISA, Western blot and other methods were used to explore the inhibitory effect of SAA on platelet and neutrophil activation.Results Compared with Ml group, SAA could improve the cardiac function and cardiac physiology changes of Ml mice, reduce the ex¬pression of CD42c in myocardial tissue and CD62p in peripheral blood without affecting tail bleeding time, reduce ADP-induced platelet activation and increase p- VASP/VASP ratio, reduce the ratio of p-PI3K/PI3K and p-AKT/AKT, reduce the expression of CD45, Ly6G, CXCL1 and CXCL2 in myocardial tissue, re¬duce the expression of complement component C3aR in myocardial tissue, and reduce C3a-induced NE and MPO, MMP9, LF level.Conclusions SAA has an anti-platelet activation effect by inhibiting the PI3K/ AKT and VASP pathways and an anti-neutrophil acti¬vation effect by inhibiting the expression of C3aR and C3a.

ObjectiveTo investigate whether there exists gender differences in mechanical pain hypersensitivity induced by the subcutaneous injection of macrophage colony-stimulating factor （M-CSF） in normal mice and to explore the preliminary mechanism. MethodsThirty 10-week-old C57BL/6J mice were randomly divided into three groups， (n = 10 mice/group, half male and half female). The albumin control group （BSA， 0.3 μg）， low dose M-CSF group （L M-CSF， 0.075 μg） and high dose M-CSF group （H M-CSF， 0.3 μg） received 50 μL BSA or M-CSF injected subcutaneously into the left medial thigh once daily for 3 consecutive days. Before and after drug administration， von-Frey mechanical sensitivity test was used to detect the mechanical paw withdrawal threshold （PWT） in each group. Immunofluorescence was performed to examine the expression changes of Ionized calcium-binding adaptor molecule 1 (Iba1) in skin， calcitonin gene-related peptide （CGRP） and phosphorylated ERK1/2 （p-ERK） in L5-L6 DRG and lumbar spinal dorsal horn. ResultsIn female mice， only high dose of M-CSF caused mechanical allodynia， whereas in male mice both doses produced marked allodynia. Mechanically， high-dose M-CSF induced massive aggregation of subcutaneous macrophages （marked by Iba1） in male and female mice， but more dramatic dependence in female mice. Similar gender differences were also found in the increase of p-ERK and CGRP expression in dorsal root ganglion （DRGs）. Notably， CGRP expression was especially elevated in the fibers of DRG in male mice. Correspondingly， the expressions of p-ERK and CGRP⁺ terminals in the superficial spinal dorsal horn of male mice were significantly higher than those of female mice after M-CSF treatment. ConclusionSubcutaneous injection of M-CSF triggers sexual dimorphism in mechanical pain hypersensitivity, which is related with differential changes in peripheral macrophage expansion and sensitization of the nociceptive pathway.

Aim To explore the effect of aucubin aucubin (AU), one of the effective ingredients of eucommia, plantain, rehmannia and other herbs, on cardiomyocyte apoptosis and cardiac function after acute myocardial infarction (MI) and the possible mechanisms. Methods In this study, the mouse models of MI were established by ligation of the anterior descending branch of the left coronary artery. Left ventricular function and the infarct size were detected using echocardiography and Masson staining. A Tumor necrosis factor-a (TNF-ot)/cycloheximide (C H X) model of cardiomyocyte injury was established, and the effects AU on myocardial injury were examined using IncuCyte live cell imaging, Western blot and TUNEL staining. Results AU administration dramatically improved cardiac function recovery and decreased infarct size after MI. AU inhibited the apoptosis of cardiomyocytes, reduced the expressions of caspase-3, and significantly increased the ratio of Bcl-2/Bax induced by TNF-ot/ CHX. Meanwhile, the estrogen receptor ß (ERß) protein level was elevated by AU, and the antiapoptotic effect of AU was blocked by ERß inhibitor. Conclusions AU can alleviate MI injury and improve cardiac function via inhibiting the apoptosis of cardiomyocytes, and its mechanism is the activation of ERß pathway.