Morphological and physiological changes in Artemisia selengensis under drought and after rehydration recovery.

Changes in global climate and precipitation patterns have exacerbated the existing uneven distribution of water, causing many plants to face the alternate situation of drought and water flooding. We studied the growth and physiological response of the wetland plant Artemisia selengensis to drought and rehydration. In this study, Artemisia selengensis seedlings were subjected to 32.89% (SD), 47.36 % (MD), 60.97% (MID), and 87.18 % (CK) field water holding capacity for 70 days, followed by 14 days of rehydration. The results showed that drought inhibited the increase of plant height, basal diameter, and biomass accumulation under SD and MD, but the root shoot ratio (R/S) increased. Drought stress also decreased the content of total chlorophyll (Chl), chlorophyll a (Chl-a), chlorophyll b (Chl-b), and carotenoid (Car). Soluble sugar (SS) and proline (Pro) were accumulated rapidly under drought, and the relative water content (RWC) of leaves was kept at a high level of 80%. After rehydration, the plant height, basal diameter, biomass, and R/S ratio could not be recovered under SD and MD, but these indicators were completely recovered under MID. The RWC, Chl, Chl-a, Chl-b, Car, and osmotic substances were partially or completely recovered. In conclusion, Artemisia selengensis not only can improve drought resistance by increasing the R/S ratio and osmotic substances but also adopt the compensatory mechanism during rehydration. It is predictable that A. selengensis may benefit from possible future aridification of wetlands and expand population distribution.

Mechanism of Bushen Jianpi decoction in preventing and treating osteoporosis caused by aromatase inhibitors in breast cancer treatment.

PURPOSE: Research on the mechanism of Bushen Jianpi decoction (BJD) for preventing and treating osteoporosis caused by aromatase inhibitors (AI) during treatment for breast cancer resection. METHODS: An ovariectomized mouse model was established using random division into 6 groups: a sham ovariectomized group, a blank control group, a control group, an alendronate group, a BJD group, and a drug combination group. Mice breast cancer cell lines (4T1) were cultured and seeded into the armpits of 6 groups of BALB/c mice. The mouse breast cancer postoperative model was built when resecting the tumor after 3 weeks following seeding tumor. After 1 weeks, the 6 groups of mice were given different drugs. Then the following analyses were made: estradiol (E2) levels and alkaline phosphatase (ALP) levels in the serum; detection of in vitro bone density and calcium and bone phosphorus content; tumor pathology and immunohistochemistry detection. RESULTS: The results suggested that BJD decreased levels of ALP in ovariectomized mice, and there was a trend for improved bone loss. BJD strengthened the trend of alendronate to improve bone loss, improved bone density, bone calcium and phosphorous, and reduced ALP. BJD had a certain role on the promotion of the expression of estrogen receptors (ERs) in the relapse of the tumor tissue. CONCLUSIONS: Combined therapy with BJD and alendronate can act synergistically against osteoporosis, which was possibly related to a reduced bone conversion rate through inhibiting bone resorption. BJD may block the MAPK signal pathway in breast cancer cells, increasing the expression of ERs and making cancer cells sensitive to endocrine treatment.

Expressions of ECE-CYC2 clade genes relating to abortion of both dorsal and ventral stamens in Opithandra (Gesneriaceae).

BACKGROUND: ECE-CYC2 clade genes known in patterning floral dorsoventral asymmetry (zygomorphy) in Antirrhinum majus are conserved in the dorsal identity function including arresting the dorsal stamen. However, it remains uncertain whether the same mechanism underlies abortion of the ventral stamens, an important morphological trait related to evolution and diversification of zygomorphy in Lamiales sensu lato, a major clade of predominantly zygomorphically flowered angiosperms. Opithandra (Gesneriaceae) is of particular interests in addressing this question as it is in the base of Lamiales s.l., an early representative of this type zygomorphy. RESULTS: We investigated the expression patterns of four ECE-CYC2 clade genes and two putative target cyclinD3 genes in Opithandra using RNA in situ hybridization and RT-PCR. OpdCYC gene expressions were correlated with abortion of both dorsal and ventral stamens in Opithandra, strengthened by the negatively correlated expression of their putative target OpdcyclinD3 genes. The complement of OpdcyclinD3 to OpdCYC expressions further indicated that OpdCYC expressions were related to the dorsal and ventral stamen abortion through negative effects on OpdcyclinD3 genes. CONCLUSION: These results suggest that ECE-CYC2 clade TCP genes are not only functionally conserved in the dorsal stamen repression, but also involved in arresting ventral stamens, a genetic mechanism underlying the establishment of zygomorphy with abortion of both the dorsal and ventral stamens evolved in angiosperms, especially within Lamiales s.l.