Zinc homeostasis in the metabolic syndrome and diabetes

Zinc(Zn)is an essential mineral that is required for various cellular functions.Zn dyshomeostasis always is related to certain disorders such as metabolic syndrome,diabetes and diabetic complications.The associations of Zn with metabolic syndrome,diabetes and diabetic complications,thus,stem from the multiple roles of Zn:(1)a constructive component of many important enzymes or proteins,(2)a requirement for insulin storage and secretion,(3)a direct or indirect antioxidant action,and(4)an insulin-like action.However,whether there is a clear cause-and-effect relationship of Zn with metabolic syndrome,diabetes,or diabetic complications remains unclear.In fact,it is known that Zn deficiency is a common phenomenon in diabetic patients.Chronic low intake of Zn was associated with the increased risk of diabetes and diabetes also impairs Zn metabolism.Theoretically Zn supplementation should prevent the metabolic syndrome,diabetes,and diabetic complications;however,limited available data are not always supportive of the above notion.Therefore,this review has tried to summarize these pieces of available information,possible mechanisms by which Zn prevents the metabolic syndrome,diabetes,and diabetic complications.In the final part,what are the current issues for Zn supplementation were also discussed.

A novel in vitro angiogenesis model based on a microfluidic device

Angiogenesis is very important for many physiological and pathological processes. However, the molecular mechanisms of angiogenesis are unclear. To elucidate the molecular mechanisms of angiogenesis and to develop treatments for "angiogenesis-dependent" diseases, it is essential to establish a suitable in vitro angiogenesis model. In this study, we created a novel in vitro angiogenesis model based on a microfluidic device. Our model provides an in vivo-like microenvironment for endothelial cells (ECs) cultures and monitors the response of ECs to changes in their microenvironment in real time. To evaluate the potential of this microfluidic device for researching angiogenesis, the effects of pro-angiogenic factors on ECs proliferation, migration and tube-like structure formation were investigated. Our results showed the proliferation rate of ECs in 3D matrix was significantly promoted by the pro-angiogenic factors (with an increase of 59.12%). With the stimulation of pro-angiogenic factors gradients, ECs directionally migrated into the Matrigel from low concentrations to high concentrations and consequently formed multi-cell chords and tube-like structures. These results suggest that the device can provide a suitable platform for elucidating the mechanisms of angiogenesis and for screening pro-angiogenic or anti-angiogenic drugs for "angiogenesis-dependent" diseases.