Linkages among stem xylem transport, biomechanics, and storage in lianas and trees across three contrasting environments.

PREMISE: Stem xylem transports water and nutrients, mechanically supports aboveground tissues, and stores water and nonstructural carbohydrates. These three functions are associated with three types of cells-vessel, fiber, and parenchyma, respectively. METHODS: We measured stem theoretical hydraulic conductivity (Kt), modulus of elasticity (MOE), tissue water content, starch, soluble sugars, cellulose, and xylem anatomical traits in 15 liana and 16 tree species across three contrasting sites in Southwest China. RESULTS: Lianas had higher hydraulic efficiency and tissue water content, but lower MOE and cellulose than trees. Storage traits (starch and soluble sugars) did not significantly differ between lianas and trees, and trait variation was explained mainly by site, highlighting how environment shapes plant storage strategies. Kt was significantly positively correlated with vessel diameter and vessel area fraction in lianas and all species combined. The MOE was significantly positively correlated with fiber area fraction, wood density, and cellulose in lianas and across all species. The tissue water content was significantly associated with parenchyma area fraction in lianas. Support function was strongly linked with transport and storage functions in lianas. In trees, transport and support functions were not correlated, while storage function was tightly linked with transport and support functions. CONCLUSIONS: These findings enhance our understanding of the relationship between stem xylem structure and function in lianas and trees, providing valuable insights into how plants adapt to environmental changes and the distinct ecological strategies employed by lianas and by trees to balance the demands of hydraulic transport, mechanical support, and storage.

Proteomic analysis of lettuce seed germination and thermoinhibition by sampling of individual seeds at germination and removal of storage proteins by polyethylene glycol fractionation.

Germination and thermoinhibition in lettuce (Lactuca sativa 'Jianyexianfeng No. 1') seeds were investigated by a proteomic comparison among dry seeds, germinated seeds at 15°C, at 15°C after imbibition at 25°C for 48 h, or at 25°C in KNO3 (all sampled individually at germination), and ungerminated seeds at 25°C, a thermoinhibitory temperature. Before two-dimensional gel electrophoresis analysis, storage proteins (greater than 50% of total extractable protein) were removed by polyethylene glycol precipitation, which significantly improved the detection of less abundant proteins on two-dimensional gels. A total of 108 protein spots were identified to change more than 2-fold (P<0.05) in abundance in at least one germination treatment. Nineteen proteins increasing and one protein decreasing in abundance during germination had higher abundance in germinated 15°C, 15°C after imbibition at 25°C for 48 h, and 25°C in KNO3 seeds than in ungerminated 25°C seeds. Gene expression of 12 of those proteins correlated well with the protein accumulation. Methionine metabolism, ethylene production, lipid mobilization, cell elongation, and detoxification of aldehydes were revealed to be potentially related to lettuce seed germination and thermoinhibition. Accumulation of three proteins and expression of five genes participating in the mevalonate (MVA) pathway of isoprenoid biosynthesis correlated positively with seed germinability. Inhibition of this pathway by lovastatin delayed seed germination and increased the sensitivity of germination to abscisic acid. MVA pathway-derived products, cytokinins, partially reversed the lovastatin inhibition of germination and released seed thermoinhibition at 25°C. We conclude that the MVA pathway for isoprenoid biosynthesis is involved in lettuce seed germination and thermoinhibition.

[Pharmacokinetic Effect of Acteoside in Blood Deficiency Rats].

Objective: To study the different pharmacokinetics effect of acteoside extracted from Rehmanniae Radix Preparata in normal and blood deficiency rats. Methods: Injected acetyl phenylhydrazine and cyclophosphamide to make blood deficiency rats models subcutaneously,and gave mice the ethand extracts of Rehmanniae Radix preparata by oral administration,the concentration of acteoside in rats at different time points were detected by HPLC method, pharmacokinetic parameters were calculated by 3p87 software. Results: The determination of acteoside in the linear range were 0. 2 ~ 80 µg / m L, the limit of detection and quantification was 0. 03 and 0. 12µg/m L,respectively. Compared with the normal group,the content of AUC0-tand AUC0-∞of corresponding dose in model group rats increased significantly, and the average dwell time and the elimination half-life prolong significantly. Conclusion: This method has high specificity,high sensitivity and simple operation, which can be used for the determination to pharmacokinetic process of acteoside in blood deficiency model.

[In vivo Pharmacokinetics of Notoginsenoside R1 in Ischemia Rats After Acute Myocardial Infarction].

OBJECTIVE: To establish an HPLC-UV method for determining pharmacokinetic difference of notoginsenoside R1 between normal rats and ischemic rats. METHODS: 48 male SD rats were randomly divided into normal group and acute myocardial ischemia( AMI) model group induced by pituitrin and each group was classified into high,middle and low-dose of groups with notoginsenoside R1 (200, 100 and 50 mg/kg) respectively. Blood samples were collected at different points in time after they were administered once by gavage and separated by Waters symmetry C18 column (250 mm x 4.6 mm, 5 µm) under the detective wavelength 203 nm, the mobile phase was acetonitrile-water with icariin as the internal standard and the pharmacokinetic parameters were calculated by DAS 2. 0. RESULTS: Notoginsenoside R1 had good linearity in the ranges of 0.2~125 µg/mL (R2 = 0.9997) with SNR 1:3 and the lowest detection limit was 0.053 µg/mL, the extraction rate, RSDs of within-day and between-day, specificity, accuracy and precision accorded with the require-ment of bio-sample pretreatment. Compared to the normal group, AUC0-t, and AUC0-∞ was significantly increased (P < 0.01) and the terminal half-life was prolonged markedly (P < 0.01) in AMI group. CONCLUSIONS: The method is simple, accurate and had high specificity and sensitivity, that could be applied in quantitative determination of notoginsenoside R1 and research of pharmacokinetics; the relative bioavailability of notoginsenoside R1 is increased significantly in AMI group,which indicates that notoginsenoside R1 has better effect in model rat.

[Analysis of volatile composition of different specification of Panax notoginseng].

OBJECTIVE: To analyse the volatile compositions of different specification of Panax notoginseng. METHODS: Volatile compositions from different specification of Panax notoginseng were detected by Headspace Solid-Phase Micro-Extraction with GC/MS. RESULTS: Terpenoids were the main compositions in different specification of Panax Notoginseng, and a-guaiene was the fundamental ingredient. The type, content and quantity of the compounds were different in different type of Panax notoginseng. CONCLUSION: Terpenoids were the main pharmacodynamics of the volatile compositions of Panax notoginseng and worthy of further study.

[Effects of Erigeron breviscapus injection on TNF-alpha, PAI-1 and tPA in rats with acute myocardial infarction].

OBJECTIVE: To research the effects of Erigeron breviscapus injection (EBI) on TNF-alpha, PAI-1 and tPA in rats with acute myocardial infarction. METHODS: Models of acute myocardial infarction (AMI)were produced by ligation of left anterior descending coronary artery, then rats were randomly divided into control and experimental groups, then respectively gavaged NS, and the low, middle and high dosage of EBI for one week. The cardiac function index and the expression of TNF-alpha, tPA and PAI-1 were measured. RESULTS: Compared with the NS group, the cardiac function LVEDP, MAP, LVPmax, +/- dp/dt of AMI rat was improved by EBI in all dosage range, and the expression of TNF-alpha and PAI-1, LVEDP were decreased (P < 0.05), the expression of tPA, MAP, LVPmax and +/- dp/dt were increased obviously (P < 0.05) and had a dose-effect relationship. CONCLUSION: EBI can inhibit the expression of TNF-alpha and PAI-1, increase the expression of tPA,which can prevent the ongoing thrombopoiesis after AMI and improve the cardiac function. This maybe attributes to the inhibition of the overexpression of TNF-alpha.

[Effects of Panax notoginseng saponins on ACE2 and TNF-alpha in rats with post-myocardial infarction-ventricular remodeling].

OBJECTIVE: To research the effects of Panax notoginseng saponins (PNS) on angiotensin-converting enzymes 2 ( ACE2) and tumor necrosis factor-alpha (TNF-alpha) in rats with post-myocardial infarction ventricular remodeling. METHODS: Models of acute myocardial infarction (AMI) were produced by ligation of left anterior descending coronary artery, 24 hours after operation the rats were randomly divided into control and experiment groups, then respectively administrated with NS, fosinopril and low, middle and high dosage of PNS for four consecutive weeks. To observe effects of PNS on malondialdehyde (MDA), nitric oxide (NO), glutathione peroxidase (GSH-Px), ACE2 and TNF-alpha in rats with post-myocardial infarction ventricular remodeling. RESULTS: Compared with NS group, MDA significantly decreased, the activity of GSH-Px significantly increased (P < 0.05 or P < 0.01), NO of the high-dose PNS group decreased (P < 0.05), Compared with the NS group, ACE2 increased and TNF-a significantly decreased in low-dose PNS group, middle and high-dose groups (P < 0.05). CONCLUSION: PNS can stimulate ACE2 to inhibit the expression of TNF-alpha and enhance the antioxidance. PNS can reduce pathological injury of cardiac myocytes in myocardial ischemia and cardiac muscle, which can improve ventricular remodeling.

How Do Structurally Distinct Compounds Exert Functionally Identical Effects in Combating Obesity?

Although the concept of inflammatory obesity remains to be widely accepted, a plethora of antibiotics, anti-inflammatory agents, mitochondrial uncouplers, and other structurally distinct compounds with unknown mechanisms have been demonstrated to exert functionally identical effects on weight reduction. Here we summarize a universal mechanism in which weight loss is modulated by mitochondrial biogenesis, which is correlated with conversion from the mitochondria-insufficient white adipose tissue to the mitochondria-abundant brown adipose tissue. This mechanistic description of inflammatory obesity may prove useful in the future for guiding pathology-based drug discovery for weight reduction.

[Effects of Panax notoginsenoside on TNF-alpha and MMP-2 expressions in rats with post-myocardial infarction ventricular remodeling and the mechanism].

OBJECTIVE: To observe the effects of Panax notoginsenoside (PNS) on tumor necrosis factor-alpha (TNF-alpha) and matrix metalloproteinases-2 (MMP-2) expressions in rats with post-myocardial infarction ventricular remodeling and explore the mechanism. METHODS: Rat models of acute infarction ventricular (AMI) were established by ligation of the left anterior descending coronary artery. Twenty-four hours after the operation, the rats were randomized into control and experimental groups for intragastric administration of normal saline (control), fosinopril and PNS at the low, medium and high doses for 4 consecutive weeks. The effects of PNS on the cardiac function index including the left ventricular end-diastolic dimension (LVIDd), left ventricular end-systolic diameter (LVIDs), ejection fraction (EF), percentage of left ventricular systole (FS), mitral early diastolic flow velocity mouth (MV), and heart rate (HR) were observed, and the changes in TNF-alpha and MMP-2 expression were detected after post-myocardial infarction ventricular remodeling. RESULTS: Compared with the control group, PNS at the medium and high doses produced significant improvements in the EF, FS and MV of the rats (P<0.01 or 0.05). TNF-alpha and MMP-2 expressions were significantly decreased by PNS treatment at low, medium and high doses (P<0.01). CONCLUSION: PNS can inhibit or reduce the expression of TNF-alpha and MMP-2, thereby enhancing left ventricular systolic and diastolic functions, decreasing peripheral resistance, and improving the cardiac function of rats with post-myocardial infarction left ventricular remodeling.