PHR1 involved in the regulation of low phosphate-induced leaf senescence by modulating phosphorus homeostasis in Arabidopsis.

Phosphorus (P) is a crucial macronutrient for plant growth, development, and reproduction. The effects of low P (LP) stress on leaf senescence and the role of PHR1 in LP-induced leaf senescence are still unknown. Here, we report that PHR1 plays a crucial role in LP-induced leaf senescence, showing delayed leaf senescence in phr1 mutant and accelerated leaf senescence in 35S:PHR1 transgenic Arabidopsis under LP stress. The transcriptional profiles indicate that 763 differentially expressed SAGs (DE-SAGs) were upregulated and 134 DE-SAGs were downregulated by LP stress. Of the 405 DE-SAGs regulated by PHR1, 27 DE-SAGs were involved in P metabolism and transport. PHR1 could bind to the promoters of six DE-SAGs (RNS1, PAP17, SAG113, NPC5, PLDζ2, and Pht1;5), and modulate them in LP-induced senescing leaves. The analysis of RNA content, phospholipase activity, acid phosphatase activity, total P and phosphate content also revealed that PHR1 promotes P liberation from senescing leaves and transport to young tissues under LP stress. Our results indicated that PHR1 is one of the crucial modulators for P recycling and redistribution under LP stress, and the drastic decline of P level is at least one of the causes of early senescence in P-deficient leaves.

Selenoprotein SELENOK Enhances the Migration and Phagocytosis of Microglial Cells by Increasing the Cytosolic Free Ca2+ Level Resulted from the Up-Regulation of IP3R.

Enhancing the migration and phagocytosis of microglial cells is of great significance for the reducing of the risk of the neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The effect of mouse selenoprotein K (mSELENOK) on the migration and phagocytosis of BV2 microglial cells and its mechanism were studied. The results showed that the over-expression of mSELENOK can increase the migratory and phagocytic abilities of the microglial cells, while the knockdown of mSELENOK can decrease the migratory and phagocytic abilities of the cells. The cytosolic free Ca2+ level and inositol trisphosphate receptor (IP3R) mRNA transcript and protein expression were also increased significantly as the consequence of the over-expression of mSELENOK in the microglial cells. On the contrary, the level of cytosolic free Ca2+ and the mRNA transcript and protein expression of IP3R in mSELENOK knockdown cells were decreased significantly. 2-aminoethoxydiphenyl borate (2-APB), an antagonist of IP3R, could prevent the increased migration, phagocytosis, and cytosolic free Ca2+ level of mSELENOK over-expressed microglial cells, and knockdown of IP3R3 could reduce the increased cytosolic Ca2+ level in mSELENOK over-expressed microglial cells. Further studies revealed that selenium supplement (Na2SeO3) can increase the expression of mSELENOK in microglial cells significantly. In summary, these data suggest that mSELENOK can increase cytosolic free Ca2+ level of microglial cells by up-regulating the expression of IP3R, thus enhancing the migration and phagocytosis of microglial cells. Our results indicated that mSELENOK is an important selenoprotein, which plays a role in trace element selenium's functions and can enhance the migration and phagocytosis of microglial cells.

Characterization of the complete chloroplast genome of Amomum longiligulare (Zingiberaceae).

Amomum longiligulare T. L. Wu (Zingiberaceae) is a herbaceous perennial grown in Hainan Province, China, which is an important medicinal plant used for the improvement of gastrointestinal motility. The complete chloroplast genome of A. longiligulare was assembled based on next-generation sequencing. The plastome was a quadripartite circular with 16,3608 bp in length, including two inverted repeat (IR, 22,696 bp) regions, one large single-copy region (LSC) and one small single-copy region (SSC) of 88,680 bp and 29,536 bp, respectively. The chloroplast genome contained 123 genes, including 85 protein-coding genes, 30 tRNA genes, and 8 rRNA genes. The overall GC content of the whole genome is 36.1%. Phylogenetic analysis strongly supported A. longiligulare and its congeneric species, A. kravanh and A. compactum, as sister group with 100% bootstrap value.

Complete chloroplast genome sequence of Swertia mileensis (Gentianaceae): a medicinal species endemic to China.

Swertia mileensis is an important medicinal plant endemic to South-east Yunnan, China, which has been widely used to treat icteric hepatitis. The complete chloroplast genome sequence of S. mileensis is presented in this study, the total size is 153,015 bp in length with a typical quadripartite structure including a pair of inverted repeat (IRs, 25,786 bp) regions separated by a large single copy (LSC, 83,048 bp) region and a small single copy (SSC, 18,395 bp) region. The overall GC content of it is 38.2%. The cp genome has 134 annotated genes, including 85 protein-coding genes, 37 tRNA genes and 8 rRNA genes. Among these genes, nine genes have one intron and two genes contain two introns. The phylogenetic tree based on 16 complete plastomes of support close relationships among two species of Swertia with 100% bootstrap value.

The complete chloroplast genome and phylogenetic analysis of Veratrum mengtzeanum Loes. F. (Liliaceae).

Veratrum mengtzeanum Loes. F. is a medicinal plant belonging to the genus Veratrum (Liliaceae). In the present study, we assembled and characterized the complete chloroplast (cp) genome of this species. The chloroplast genome is 152,051 bp in length, with one large single copy (LSC) region and one small single copy (SSC) region of 82,112 bp and 17,544 bp, respectively; two inverted repeat (IR) regions of 26,198 bp. It contains 131 annotated genes, including 85 protein-coding genes (PCGs), 38 transfer RNA (tRNA) genes, and 8 ribosomal RNA (rRNA) genes. Phylogenetic analysis indicated that V. mengtzeanum was closely related to Veratrum japonicum with 100% bootstrap value.

Icariin ameliorates cisplatin-induced cytotoxicity in human embryonic kidney 293 cells by suppressing ROS-mediated PI3K/Akt pathway.

Cisplatin, as an effective chemotherapeutic agent, is widely used to treat verious types of cancers. Nephrotoxicity induced by cisplatin seriously limits its clinical application. Icariin, a major and remarkable flavonoid isolated from Epimedium koreanum, has been reported to exert anti-oxidative stress and anti-inflammation actions. The purpose of this study is to explore the protective effect and possible mechanism of icariin on cisplatin-induced nephrotoxicity on HEK-293 cells. In this study, icariin pretreatment for 24 h significantly ameliorated cisplatin-induced oxidative stress by reducing levels of malondialdehyde (MDA) and reactive oxygen species (ROS), while increasing level of glutathione (GSH) in HEK-293 cells. Furthermore, icariin pretreatment reduced NF-κB phosphorylation and nuclear translocation in HEK-293 cells followed by decreased secretion of IL-1ß, TNF-α, and iNOS, suggesting a suppression of inflammatory response. Moreover, icariin pretreatment significantly reduced cellular apoptosis via reduced levels of Bax, cleaved caspase-3/9, and increased anti-apoptotic protein Bcl-2 in the cells. Importantly, LY294002, a specific PI3K inhibitor, abrogated the anti-apoptosis effect of icariin, implicating the involvement of PI3K/Akt pathway. In summary, icariin prevents cisplatin-induced HEK-293 cell injury by inhibiting oxidative stress, inflammatory response, and cellular apoptosis partly via regulating NF-κB and PI3K/Akt signaling pathways. Icariin may serve as a potential therapeutic target against cisplatin-induced nephrotoxicity.

Improvement of Cisplatin-induced renal dysfunction by Schisandra chinensis stems via anti-inflammation and anti-apoptosis effects.

ETHNOPHARMACOLOGICAL RELEVANCE: Schisandra chinensis (Turcz.) Baill is a frequently used traditional Chinese medicine, and modern pharmacological research has proven that S. chinensis has antioxidant, anti-hepatotoxity, anti-inflammatory, and anti-nephrotoxic effects. Cisplatin is widely used as antineoplastic drug at present, but the clinical application is limited owing to its nephrotoxicity. AIM OF THE STUDY: To demonstrate the renoprotective activity of the extract of the stems of S. chinensis (SCE) in mice established by cisplatin-triggering acute kidney injury (AKI). The possible molecular mechanism of nephroprotection exhibited by SCE was evaluated for the first time. MATERIALS AND METHODS: Mice in SCE groups were pre-treated with SCE for 10 consecutive days, and on 7th day 1 h after final administration, following intraperitoneal injection of cisplatin with 20 mg/kg was treated to cisplatin group and SCE groups. On the 10th day, renal function, histopathological change, and oxidative stress markers were investigated. RESULTS: Renal oxidative stress level characterized by elevated heme oxygenase 1 (HO-1), cytochrome P450 E1 (CYP2E1) and 4-hydroxynonenal (4-HNE) expression was obviously reduced by SCE pre-treatment. In addition, SCE was found to suppress inflammatory response through the reduction of nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) expression and nuclear factor-kappa B (NF-κB) p65 activation. SCE treatment also inhibited activation of apoptotic pathways through down-regulating Bax, cleaved caspase-3, 8, 9 and up-regulating Bcl-2 expression levels. CONCLUSION: These findings illustrated that SCE possessed powerful protective effect on AKI caused by cisplatin via amelioration of oxidative stress, inflammation and apoptosis.

Three New Triterpenoid Saponins from Notoginseng Medicinal Fungal Substance.

Three new triterpenoid saponins, named ginsenoside-Rh23 (1), ginsenoside-Rh24 (2), and ginsenoside-Rh25 (3), were isolated from notoginseng medicinal fungal substance. Their structures were elucidated by a combination of 1D- and 2D-NMR, MS and chemical analysis. Compounds 1 - 3 exhibited moderate cytotoxic activity against MCF-7 and NCI-H460 cancer cell lines.

Differential expression of VGLUT1 or VGLUT2 in the trigeminothalamic or trigeminocerebellar projection neurons in the rat.

The vesicular glutamate transporters, VGLUT1 and VGLUT2, reportedly display complementary distribution in the rat brain. However, co-expression of them in single neurons has been reported in some brain areas. We previously found co-expression of VGLUT1 and VGLUT2 mRNAs in a number of single neurons in the principal sensory trigeminal nucleus (Vp) of the adult rat; the majority of these neurons sent their axons to the thalamic regions around the posteromedial ventral nucleus (VPM) and the posterior nuclei (Po). It is well known that trigeminothalamic (T-T) projection fibers arise not only from the Vp but also from the spinal trigeminal nucleus (Vsp), and that trigeminocerebellar (T-C) projection fibers take their origins from both of the Vp and Vsp. Thus, in the present study, we examined the expression of VGLUT1 and VGLUT2 in Vp and Vsp neurons that sent their axons to the VPM/Po regions or the cortical regions of the cerebellum. For this purpose, we combined fluorescence in situ hybridization (FISH) histochemistry with retrograde tract-tracing; immunofluorescence histochemistry was also combined with anterograde tract-tracing. The results indicate that glutamatergic Vsp neurons sending their axons to the cerebellar cortical regions mainly express VGLUT1, whereas glutamatergic Vsp neurons sending their axons to the thalamic regions express VGLUT2. The present data, in combination with those of our previous study, indicate that glutamatergic Vp neurons projecting to the cerebellar cortical regions express mainly VGLUT1, whereas the majority of glutamatergic Vp neurons projecting to the thalamus co-express VGLUT1 and VGLUT2.