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Objective: To observe the changes of Prohibitin1(PHB1) contents in rat brain, heart, skeletal muscle tissue and mitochondria with acute exhaustive exercise and the effects of acute exhaustive exercise on mitochondrial function in rats, to explore the relationship among PHB1 and mitochondrial function and energy metabolism., Methods: Acute exhaustive exercise model:The rats carried acute exhaustive exercise after 8 weeks of feeding. The heart, brain and skeletal muscle samples were collected and the mitochondria were collected to detect the changes of respiratory function and reactive oxygen species(ROS). The expression of PHB1 protein in tissues and mitochondria was detected by Western blot. The ATP content in the organs and the activity of complexes (ATP synthase activity) in mitochondria were measured by spectrophotometer., Results: ① The ATP contents of brain, myocardium and skeletal muscle were decreased significantly after acute exhaustive exercise. ②The activities of complex V, respiratory control rates (RCR) and ROS in mitochondria of brain, myocardium and skeletal muscle were decreased significantly after acute exhaustive exercise, respiration rate state 4(ST4) was increased significantly, at the same time, respiration rate state 3(ST3) had no significant difference. ③ The expression of PHB1 in mitochondria of skeletal muscle was decreased significantly after acute exhaustive exercise, while there was no significant change in PHB1 in myocardial tissue and mitochondria. ④ The correlation analysis showed that the ATP contents in the brain, myocardium and skeletal muscle were positively correlated with the activity of complex V and the expression of PHB1 after acute exhaustive exercise., Conclusions: After acute exhaustive exercise, the mitochondrial oxidative phosphorylation was reduced, the ROS production was increased, the expression of PHB1 was decreased, the ATP content and the activity of complex V were decreased in the brain and skeletal muscle of rats. Acute exhaustive exercise reduced the expression of PHB1 in mitochondria, decreased mitochondrial function, and reduced energy metabolism.

The present study is aimed to investigate the in vitro metabolic interconversion between baicalin (BG) and baicalein (B) in rat liver, kidney, intestine and bladder. BG and B were separately incubated with rat hepatic, renal, and intestinal microsomes, as well as bladder homogenates, for 30 min. The metabolites were identified and quantified by HPLC and metabolic kinetic parameters were obtained by fitting the data to the Michaelis-Menten equation. In hepatic microsomes, renal microsomes and bladder homogenates, but not in intestinal microsomes, BG was transformed into B, the hydrolysis metabolite of BG, with K(m) values being (44.65 +/- 6.01), (92.73 +/- 11.41), (74.60 +/- 3.68) micromol x L(-1), respectively, and V(max) values being (12.32 +/- 0.56), (3.30 +/- 0.18), (5.93 +/- 0.12) micromol x min(-1) x g(-1) (protein), respectively. In incubations with hepatic, renal, and intestinal microsomes and bladder homogenates, B was also transformed into BG, the glucuronidation metabolite of B, with K(m) values being (67.46 +/- 10.49), (226.7 +/- 71.59), (177.3 +/- 35.85), and (18.33 +/- 2.53) micromol x L(-1), respectively, and V(max) values being (14.74 +/- 0.97), (5.91 +/- 1.03), (38.14 +/- 3.60), and (1.22 +/- 0.05) micromol x min(-1) x g(-1) (protein), respectively. The results showed that the activity of UDP-glucuronosyltranferase (UGT) in intestinal microsomes was the highest among the four organs, and the activities of UGT were higher than that of glucuronidase (GUS) in hepatic, renal and intestinal microsomes, but the activity of GUS was higher than that of UGT in bladder homogenates.

To study the pharmacokinetics of flavonoids from Xiexin decoction in rats. SD rats were given a single ig dose of Xiexin decoction 12 g x kg(-1), plasma and urine were collected before and after dosing. Flavonoids components in plasma and urine were measured by HPLC. Pharmacokinetic parameters were determined from the plasma concentration-time data and urinary excretion-time data with the DAS software package. Baicalin was incubated with the rat renal homogenate to investigate its metabolism in vitro. After oral administration of Xiexin decoction baicalin and wogonoside were quickly absorbed and exhibited double peak phenomena in their plasma concentrations. The first peaks in plasma concentrations of baicalin and wogonoside reached Cmax1 of (10 +/- 8) and (1.5 +/- 0.5) mg x L(-1) at Tmax1 of (0.27 +/- 0.09) and (0.17 +/- 0.00) h, while the second peaks reached Cmax2 of (3. 9 0. 5) and (0. 74 +/- 0.11) mg x L(-1) at Tmax2 of (7.6 +/- 2.6) and (16.0 +/- 0.0) h, respectively. The T(1/2) of baicalin and wogonoside were (7 +/- 3) and (6.4 +/- 2.1) h, AUC(0-infinity) were (57 +/- 12) and (15 +/- 3) mg x h x L(-1), respectively. After oral administration of Xiexin decoction, not only baicalin and wogonoside but also baicalein and wogonin can be detected in the urine. The amounts of baicalin, wogonoside, baicalein and wogonin excreted from urine during 0-72 h were (1.4 +/- 0.3), (3.4 +/- 1.3), (2.2 +/- 0.97), (10 +/- 4)% of dose given in rats, respectively. The excretion T(1/2) of the four flavonoids were (6.9 +/- 2.1), (9 +/- 4) , (8.2 +/- 2.0) and (7.2 +/- 1.8) h, respectively. Baicalin was metabolized into baicalein in the rat renal homogenate in vitro, and the kinetic parameters were measured as Vmax = 702 nmol x min(-1) x g(-1) (protein) and Km=135 micromol x L(-1). After oral administration of Xiexin decoction, flavonoids can be absorbed quickly. Only a small quantity of baicalin, wogonoside, baicalein and wogonin were excreted from urine. Baicalin may be metabolized into baicalein in the rat kidney.

Agroinfiltration is a newly developed plant transient gene expression technique, which is simple, rapid and reproducible. It has been widely used in analyses of foreign gene expression, hypersensitive reaction, gene silencing, promoter activity and identification of new disease-resistance genes. In this paper, we describe the principle and the operation procedure of Agroinfiltration and its application in diverse aspects of plant molecular biology research. Our experiences in modification of the Agroinfiltration technique are also provided.