Hydrophobicity Regulation of Energy Acceptors Confined in Mesoporous Silica Enabled Reversible Activation of Optogenetics for Closed-Loop Glycemic Control.

Optogenetics-based synthetic biology holds great promise as a cell-based therapy strategy for many clinical incurable diseases; however, precise control over genetic expression strength and timing through disease state-related closed-loop regulation remains a challenge due to the lack of reversible probes to indicate real-time metabolite fluctuations. Here, based on a novel mechanism of analyte-induced hydrophobicity regulation of energy acceptors confined in mesoporous silica, we developed a smart hydrogel platform comprising glucose reversible responsive upconversion nanoprobes and optogenetic engineered cells, in which the upconverted blue light strength was adaptively tuned through blood glucose levels to control optogenetic expressions for insulin secretion. The intelligent hydrogel system enabled convenient maintenance of glycemic homeostasis through simple near-infrared illuminations without any additional glucose concentration monitoring, which efficiently avoided genetic overexpression-induced hypoglycemia. This proof-of-concept strategy efficiently combines diagnostics with optogenetics-based synthetic biology for mellitus therapy, opening up a new avenue for nano-optogenetics.

Phenoloxidase, an effective bioactivity target for botanical insecticide screening from green walnut husks.

Phenoloxidase, a critical enzyme in insects, may serve as a promising target in botanical insecticide development. In an effort to identify active ingredients with insecticidal properties in green walnut husks, juglone and plumbagin were isolated from the chloroform extract using phenoloxidase as bioactive target with the IC50 of 0.247 g/L and 0.256 g/L, respectively. After an artificial diet feeding of the juglone or plumbagin, more than 50% corrected mortality in stomach toxicity form was observed in Pieris rapae Linne larvae and Helicoverpa armigera Hübner larvae at the concentration ≥0.01 g/L, the LC50 of juglone and plumbagin for two kinds of insects were determined as 0.012, 0.011 and 0.022, 0.030 g/L, respectively. This research indicated the significance of PO as bioactive target in pesticides identification and also shed light on the development of phenoloxidase inhibitor as promising botanical insecticides in the future.

Senobtusin, a novel alkaloid with amidine moiety from Senecio obtusatus Wall. ex DC.

Phytochemical investigation of Senecio obtusatus Wall. ex DC led to the isolation of a novel alkaloid, senobtusin (1). Compound 1 possesses an atypical amidine moiety, and the structure was determined on the basis of extensive NMR analysis and HR-ESI-MS technique. This is the first report of this class of natural products obtained from family Asteraceae, and the systematic importance was also discussed.

[Effects of silverionized drinking water on lipids metabolism in tail-suspended rats].

OBJECTIVE: To study the effect of silverionized drinking water on erythrocyte membrane fluidity, serum lipids and vascular endothelial cells in tail-suspended rats. METHOD: Thirty male SD rats were randomly divided into ground control group (GC), simulated weightlessness control group (SC), simulated weightlessness and silverionized water drinking group (SS). Number of circulating endothelial cells (CEC), serum lipids and erythrocyte membranes fluidity was measured on the 21st day of tail suspension. RESULT: Levels of serum TC, TG, HDL-C, HDL-C/TC and erythrocyte membrane fluidity in SC rats were significantly lower than those in GC rats; LDL-C/HDL-C ratio and number of CEC in SC rats were markedly higher than those in GC rats. Levels of serum TC, LDL-C and LDL-C/HDL-C in SS rats were higher than those in SC rats; HDL-C/TC ratio and erythrocyte membrane fluidity in SS rats were lower than those in SC rats. CONCLUSION: Drinking silverionized water has a negative effect on lipid metabolism in tail-suspended rats.

[Effects of spirulina on serum lipids, erythrocyte membrane fluidity and vascular endothelial cells in tail-suspended rats].

OBJECTIVE: To study the changes of erythrocyte membrane fluidity, serum lipid and vascular endothelial cell caused by simulated weightlessness in rats and the beneficial effect of spirulina. METHOD: Thirty male SD rats were divided into 3 groups: free control group (group A) and two simulated weightlessness groups (groups B, C). Rats in group A and B were fed with normal forage, and the rats in group C were fed with normal forage supplemented with 5% (W/W) spirulina. Water was taken ad libitum. RESULT: Levels of serum CHO, HDL, TG, HDL-C/CHO and erythrocyte membrane fluidity decreased significantly, and number of vascular endothelial cells in plasma increased markedly in group B as compared with those in group A; The ratio of LDL-C/HDL-C, and atherosclerosis index (AI) decreased, number of vascular endothelial cells significantly lowered; level of CHO, HDL-C and value of the IDmax of plasma as well as erythrocyte membrane fluidity remarkedly increased in group C compared with those in group B. CONCLUSION: Spirulina can improve the physiological conditions of erythrocyte membrane fluidity, serum lipid and vascular endothelial cell caused by simulated weightlessness in rats.

[Effects of dietary n-3 polyunsaturated fatty acid on lipid metabolism in rats under simulated weightlessness].

Objective. To study the effect of dietary n-3 polyunsaturated fatty acid (PUFA) on the lipid metabolism of tail-suspended rats. Method. 49 male Sprague-Dawley rats were divided into five groups: tail-suspension group I, fed with 10 wt % corn oil, tail-suspension groups II, III, IV were fed with three levels of fish oil (0.5, 1.5 or 3.0 wt %; low, middle and high level of fish oil, respectively). Group V fed with 10 wt % corn oil served as normal control. Result. Viscoelasticity of cell membrane in group III was significantly higher than that of group I (P<0.01); Vascular endothelial cells (VEC) was less in group II compared to group I; Serum total cholesterol (TC) and triglyceride (TG) , serum lipoprotein were lower in groups II, III, IV compared to group I, the higher fish oil content in diet, the lower serum lipid concentration in microgravity. Conclusion. Dietary n-3 PUFA do have distinguished effect on lipid metabolism and n-3 PUFA have certain effects on prevention of atherosclerotic disease and coronary heart disease in rats.