Cloning and morphological properties of Nicgl;CYCD3;1 gene in genetic tumors from interspecific hybrid of N. langsdorffii and N. glauca.

Plant genetic tumors represent neoplastic growths, which arise spontaneously in hybrid plants without apparent external induction. To understand the molecular nature of unregulated cell proliferation, a cyclin D cDNA clone encoding a cyclin D of 1104bp was isolated from a genetic tumor and designated Nicgl;CYCD3;1 gene. DNA gel blot analysis suggested that there are two copies of Nicgl;CYCD3;1 in the genetic tumors. Northern analysis showed that this gene had the highest expression level in genetic tumor compared to Nicotiana glauca, N. langsdorffii and hybrid plants. Plant morphology of hybrid plant was an intermediate between N. glauca and N. langsdorffii and was altered in the genetic tumors. The cell cycle distribution in N. glauca was G0/G1, 90.59; S, 0.60; G2/M, 8.81; in N. langsdorffii it was G 0/G1, 86.22; S, 6.90; G2/M, 6.88; in hybrid plants it was G 0/G1, 96.40; S, 1.79; G2/M, 1.81; and in genetic tumors G 0/G1, 74.70; S, 2.35; G2/M, 22.94. These data provide new insights into the molecular mechanisms underlying genetic tumor formation from interspecific hybrid between N. langsdorffii and N. glauca.

Antidiabetic properties of 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene from mulberry (Morus bombycis koidzumi) root in streptozotocin-induced diabetic rats.

We investigated the antidiabetic properties of 2,5-dihydroxy-4,3-di(beta-D-glucopyranosyloxy)-trans-stilbene (DGTS) isolated from Morus bombycis Koidzumi in streptozotocin (STZ)-induced diabetic rats. The DGTS prevented the increase in aspartate aminotransferase, alanine aminotransferase, and blood urea nitrogen levels in serum of diabetic rats. At doses of 200-800 mg/kg, DGTS improved hyperglycemia in the rats, and the hypoglycemic effect of DGTS was comparable to that of tolbutamide. The histological observations showed that DGTS prevented atrophy of pancreatic beta-cells and vascular degenerative changes in the islets. DGTS reversed STZ-induced diabetes and had antioxidant activity in assays of FeCl(2)/ascorbic acid-induced lipid peroxidation in the rats. Levels of cytochrome P450 2E1 mRNA, as measured by reverse transcription-polymerase chain reaction, were lower in the livers of the DGTS-treated rats than those of the control group. These results suggest that DGTS might be beneficial in the treatment of type 1 diabetes.

[Attributes of forest infrastructure].

This paper discussed the origin and evolution of the conception of ecological infrastructure, the understanding of international communities about the functions of forest, the important roles of forest in China' s economic development and ecological security, and the situations and challenges to the ongoing forestry ecological restoration programs. It was suggested that forest should be defined as an essential infrastructure for national economic and social development in a modern society. The critical functions of forest infrastructure played in the transition of forestry ecological development were emphasized. Based on the synthesis of forest ecosystem features, it was considered that the attributes of forest infrastructure are distinctive, due to the fact that it is constructed by living biological material and diversified in ownership. The forestry ecological restoration program should not only follow the basic principles of infrastructural construction, but also take the special characteristics of forests into consideration in studying the managerial system of the programs. Some suggestions for the ongoing programs were put forward: 1) developing a modern concept of ecosystem where man and nature in harmony is the core, 2) formulating long-term stable investments for forestry ecological restoration programs, 3) implementing forestry ecological restoration programs based on infrastructure construction principles, and 4) managing forests according to the principles of infrastructural construction management.

Identification and properties of 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene from Morus bombycis Koidzumi roots.

2,5-Dihydroxy-4,3'-di(beta-d-glucopyranosyloxy)-trans-stilbene was identified from Morus bombycis Koidzumi roots. The 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene at a dose of 400-600 mg/kg had hepatoprotective activity comparable to the standard agent, silymarin. The biochemical assays were confirmed by histological observations showing that the 2,5-dihydroxy-4,3'-di(beta-d-glucopyranosyloxy)-trans-stilbene from Morus bombycis Koidzumi roots decreased cell ballooning in response to CCl4 treatment. These results demonstrate that the 2,5-dihydroxy-4,3'-di(beta-d-glucopyranosyloxy)-trans-stilbene component has a liver protective action against CCl4-induced hepatotoxicity.

Antioxidant effects and hepatoprotective activity of 2,5-dihydroxy-4,3'-di(beta-d-glucopyranosyloxy)-trans-stilbene from Morus bombycis Koidzumi roots on CCl4-induced liver damage.

We investigated hepatoprotective activity and antioxidant effect of the 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene that purified from Morus bombycis Koidzumi roots against CCl4-induced liver damage in rats. The 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene displayed dose-dependent superoxide radical scavenging activity (IC50 = 430.2 microg/ml), as assayed by the electron spin resonance (ESR) spin-trapping technique. The increase in aspartate aminotransferase (AST) activities in serum associated with carbon tetrachloride (CCl4)-induced liver injury was inhibited by 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene and at a dose of 400 - 600 mg/kg samples had hepatoprotective activity comparable to the standard agent, silymarin. The biochemical assays were confirmed by histological observations showing that the 2,5-dihydroxy-4,3'-di(beta-d-glucopyranosyloxy)-trans-stilbene decreased cell ballooning in response to CCl4 treatment. These results demonstrate that the 2,5-dihydroxy-4,3'-di(beta-D-glucopyranosyloxy)-trans-stilbene is a potent antioxidant with a liver protective action against CCl4-induced hepatotoxicity.

Free radical scavenging and hepatoprotective actions of Quercus aliena acorn extract against CCl4-induced liver.

In the present study, we investigated the protective effect of Quercus aliena acorn extracts against CCl4-induced hepatotoxicity in rats, and the mechanism underlying the protective effects. Aqueous extracts of Quercus aliena acorn had higher superoxide radical scavenging activity than other types of extracts. The Quercus aliena acorn extracts displayed dose-dependent superoxide radical scavenging activity (IC50 = 4.92 microg/ml), as assayed by the electron spin resonance (ESR) spin-trapping technique. Pretreatment with Quercus aliena acorn extracts reduced the increase in serum aspartate aminotransferase (AST) and serum alanine aminotransferase (ALT) levels. The hepatoprotective action was confirmed by histological observation. The aqueous extracts reversed CCl4-induced liver injury and had an antioxidant action in assays of FeCl2- ascorbic acid induced lipid peroxidation in rats. Expression of cytochrome P450 2E1 (CYP2E1) mRNA, as measured by RT-PCR, was significantly decreased in the livers of Quercus aliena acorn-pretreated rats compared with the livers of the control group. These results suggest that the hepatoprotective effects of Quercus aliena acorn extract are related to its antioxidative activity and effect on the expression of CYP2E1.

Hepatoprotective and antioxidant effects of Morus bombycis Koidzumi on CCl4-induced liver damage.

The antioxidant activity and liver protective effect of Morus bombycis Koidzumi were investigated. Aqueous extracts of M. bombycis Koidzumi had higher superoxide radical scavenging activity than other types of extracts. The aqueous extract at a dose of 100 mg/kg showed significant hepatoprotective activity when compared with that of a standard agent. The biochemical results were confirmed by histological observations indicating that M. bombycis Koidzumi extract together with CCl(4) treatment decreased ballooning degeneration. The water extract recovered the CCl(4)-induced liver injury and showed antioxidant effects in assays of FeCl(2)-ascorbic acid-induced lipid peroxidation in rats. Based on these results, we suggest that the hepatoprotective effect of the M. bombycis Koidzumi extract is related to its antioxidative activity.