24β-Ethyl-31-norlanosta-8,25(27)-dien-3β-ol and 24β-ethyl-25(27)-dehydrolophenol in seeds of three cucurbitaceae species

The structures of two 4α-methylsterols is isolated from Cucumis sativus(Cucurbitaceae) seeds were determined based mainly on their ¹³CNMR spectra as 24β-ethyl-31-norlanosta-8,25(27)-dien-3β-ol and 24β-ethyl-25(27)- dehydrolophenol, respectively, of which the former is a new sterol from natural sources. These two 4α-methylsterols were identified in the seeds of two other Cucurbitaceae species, Lagenaria leucantha var. Gourda and Citrullus battich. The probable biogenetic significance of the two 4α-methylsterols is discussed. Other 4α-methylsterols identified in the seeds of the three Cucurbitaceae species were obtusifoliol, cycloeucalenol and gramisterol.     

Hormonal effects on diosgenin biosynthesis and growth in Dioscorea deltoidea tissue cultures

Analysis of Dioscorea deltoidea tissue cultures grown in the presence of 2,4-D, indole-3-butyric acid, isopentenyladenine, benzyladenine and GA singly and in combination showed that the medium with 2,4-D most consistently favored diosgenin production. GA and high benzyladenine concentrations were toxic.     

Listeria monocytogenes induces host DNA damage and delays the host cell cycle to promote infection

Listeria monocytogenes (Lm) is a human intracellular pathogen widely used to uncover the mechanisms evolved by pathogens to establish infection. However, its capacity to perturb the host cell cycle was never reported. We show that Lm infection affects the host cell cycle progression, increasing its overall duration but allowing consecutive rounds of division. A complete Lm infectious cycle induces a S-phase delay accompanied by a slower rate of DNA synthesis and increased levels of host DNA strand breaks. Additionally, DNA damage/replication checkpoint responses are triggered in an Lm dose-dependent manner through the phosphorylation of DNA-PK, H2A.X, and CDC25A and independently from ATM/ATR. While host DNA damage induced exogenously favors Lm dissemination, the override of checkpoint pathways limits infection. We propose that host DNA replication disturbed by Lm infection culminates in DNA strand breaks, triggering DNA damage/replication responses, and ensuring a cell cycle delay that favors Lm propagation.     

Supplemental vitamin D increases serum cytokines in those with initially low 25-hydroxyvitamin D: A randomized,double blind,placebo-controlled study

The purpose of this study was to determine if vitamin D status before supplementation influences the cytokine response after supplemental vitamin D. Forty-six reportedly healthy adults (mean(SD); age, 32(7) y; body mass index (BMI), 25.3(4.5) kg/m²; serum 25-hydroxyvitamin D (25(OH)D), 34.8(12.2) ng/mL) were randomly assigned (double blind) to one of three groups: (1) placebo (n = 15), or supplemental vitamin D (cholecalciferol) at (2) 4000 (n = 14) or (3) 8000 IU (n = 17). Supplements were taken daily for 35 days. Fasting blood samples were obtained before (Baseline, Bsl) and 35-days after (35-d) supplementation. Serum 25(OH)D, 1,25-dihydroxyvitamin D (1,25(OH)D), cytokines, and intact parathyroid hormone with calcium were measured in each blood sample. Supplemental vitamin D increased serum 25(OH)D (4000 IU, ≈29%; 8000 IU, ≈57%) and 1,25(OH)D (4000 IU, ≈12%; 8000 IU, ≈38%) without altering intact parathyroid hormone or calcium. The vitamin D metabolite increases in the supplemental vitamin D groups (n = 31) were dependent on initial levels as serum 25(OH)D (r = −0.63, p < 0.05) and 1,25(OH)D (r = −0.45, p < 0.05) at Bsl correlated with their increases after supplementation. Supplemental vitamin D increased interferon (IFN)-γ and interleukin (IL)-10 in subjects that were vitamin D insufficient (serum 25(OH)D < 29 ng/mL) compared to sufficient (serum 25(OH)D ⩾ 30 ng/mL) at Bsl. We conclude that supplemental vitamin D increase a pro- and anti-inflammatory cytokine in those with initially low serum 25(OH)D.     

Formation of cartilage by non-chondrogenic cell types

Freshly excised embryonic rat skeletal muscle has been shown to form hyaline cartilage when organ cultured upon demineralized rat bone (bone matrix). Since skeletal muscle is composed of fibrous connective tissue (C.T.) as well as muscle cells, the cartilage could arise from either of these sources. The object of this study was to determine whether cartilage arose from fibrous connective tissue or muscle cells, or both, and whether the ability to form cartilage is limited to tissues derived from somatic mesoderm. Control experiments demonstrated that 19-day embryonic rat skeletal muscle formed cartilage when organ cultured on bone matrix after dissociation and cultivation in vitro, and that 11-day embryonic chick muscle also formed cartilage, although less reproducibly (3 out of 10 cases). Fibroblasts and skeletal muscle were cloned from similar suspensions of dissociated muscle in order to test these purified cell types. Dermis, vascular tissue, and tendons were mechanically removed prior to dissociation in order to eliminate fibroblasts from contaminant sources. Cloned fibroblasts, derived from rat skeletal muscle, formed cartilage in three out of three cases. It was not possible to clone sufficient rat skeletal muscle to place an aggregate onto bone matrix. An aggregate of several hundred chick skeletal muscle clones formed cartilage on bone matrix. The freshly excised C.T. capsules of embryonic chick thyroid and lung were tested for the ability to form cartilage as nonskeletal C.T. derivatives. The epithelial rudiments of thyroid and lung were also tested as endodermal derivatives. Chick cornea was similarly tested as an ectodermal derivative. Of these tissues, only the C.T. capsules formed cartilage. The results demonstrate that various C.T. cell types may alter their phenotype well after that stage at which their differentiation is thought to be stabilized, and that the ability to differentiate as cartilage may be common to all C.T. cells. The option of differentiating along a certain variety of pathways may depend more upon local conditions than on a predetermined pattern.     

Seasonal variation and correlation analysis of vitamin D and parathyroid hormone in Hangzhou,Southeast China

This study aimed to describe the 25‐hydroxyvitamin D (25(OH)D) and parathyroid hormone (PTH) status of Southeast Chinese individuals influenced by season. The secondary aim was to determine the cutoff for sufficient 25(OH)D in a four‐season region. From January 2011 to June 2014, a total of 17 646 individuals were evaluated in our study. The serum levels of PTH were detected simultaneously in 5579 cases. A total of 25(OH)D and intact PTH were measured by the electrochemiluminescent immunoassay. The distribution of the concentration, prevalence and seasonal variability of 25(OH)D and PTH were studied. The mean 25(OH)D concentration in our study was 43.00(30.40) nmol/L. The prevalence of insufficiency (25(OH)D < 50 nmol/L) was 62.87% and that of deficiency (<30 nmol/L) was 28.54%. Mean serum 25(OH)D levels revealed a limited sinusoidal profile throughout the year and were significantly higher in Autumn. On the other hand, PTH levels showed an opposite response to seasonal effects relative to 25(OH)D. Age, BMI and daylight were not significantly correlated with 25(OH)D and serum PTH reached a plateau at higher values of serum 25(OH)D of 42.86 nmol/L. This study demonstrated that Vitamin D insufficiency is highly prevalent in Southeast China. The concentration of 25(OH)D in the male group was generally higher than that in the female group. Seasonal variation was an important aspect of 25(OH)D and PTH concentration. This study revealed that the optimal serum threshold of 25(OH)D for bone health should be between 40 and 50 nmol/L for Southeast Chinese individuals.     

Lipid status association with 25-hydroxy vitamin D: Cross sectional study of end stage renal disease patients

BackgroundSome observational studies indicate an association of 25-hydroxy vitamin D (25(OH)D) insufficiency and atherogenic cholesterol concentrations. The aim of this study was to investigate relationship between 25(OH)D concentrations and lipid parameters in end stage renal disease (ESRD) patients, separately for predialysis, hemodialysis and peritoneal dialysis patients.MethodsWe have adjusted 25(OH)D concentrations for seasonal variability with cosinor analysis, and performed all further analysis using these corrected 25(OH)D concentrations. Concentrations of 25(OH)D and the lipid parameters were determined in 214 ESRD patients and 50 control group participants. The analysis included the measurement of 25(OH)D by HPLC, apolipoprotein (Apo) AI, ApoB and Lp(a) by nephelometry, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) by spectrophotometry and manually calculated ApoB/ApoAI and LDL-C/HDL-C ratio.ResultsESRD patients with adjusted 25(OH)D concentrations of 50 nmol/L had significantly higher TC (P = 0.005) and ApoAI (P = 0.049). Significantly higher HDLC (P = 0.011) and ApoAI (P = 0.020) were found in hemodialysis patients with the 25(OH)D concentrations of 50 nmol/L. The other analyzed lipid parameters differed significantly between predialysis, hemodialysis and peritoneal dialysis patients with 25(OH)D concentrations of < 50 nmol/L.ConclusionsOur study indicate the significant relationship between 25(OH)D repletion and optimal concentrations of lipid parameters in ESRD patients. Further research is necessary to explain whether joint evaluation of vitamin D status and lipid abnormalities could improve cardiovascular outcome in ESRD patients.     

NbALY916 is involved in potato virus X P25-triggered cell death in Nicotiana benthamiana

Systemic necrosis often occurs during viral infection of plants and is thought mainly to be the result of long-term stress induced by viral infection. Potato virus X (PVX) encodes the P25 pathogenicity factor that triggers a necrotic reaction during PVX-potato virus Ysynergistic coinfection. In this study, we discovered that NbALY916, a multifunctional nuclear protein, could interact with P25. When NbALY916 expression was reduced by tobacco rattle virus (TRV)-based virus-induced gene silencing, the accumulation of P25 was increased, which would be expected to cause more severe necrosis. However, silencing of NbALY916 reduced the extent of cell death caused by P25. Furthermore, we found that overexpression of NbALY916 increased the accumulation of H₂O₂ and triggered more extensive cell death when coexpressed with P25, even though accumulation of P25 was itself reduced by the increased expression of NbALY916. Furthermore, transient expression of P25 specifically induced the expression of NbALY916 mRNA, but not the mRNAs of three other ALYs in Nicotiana benthamiana. In addition, we showed that silencing of NbALY916 or transient overexpression of NbALY916 affected the infection of PVX in N. benthamiana. Our results reveal that NbALY916 has an antiviral role that, in the case of PVX, operates by inducing the accumulation of H₂O₂ and mediating the degradation of P25.     

Adoptive transfers of CD4+CD25+ Tregs partially alleviate mouse premature ovarian insufficiency

This study was designed to investigate the protective effect of CD4⁺CD25⁺ regulatory T cells (Tregs) against zona pellucida glycoprotein 3 peptide (pZP3) immunization‐induced premature ovarian insufficiency (POI) in mice. A mouse POI model was induced by two subcutaneous injections of pZP3 (50 nmol/L). Mice in the pZP3‐Treg group were intraperitoneally injected with 5 × 10⁵ CD4⁺CD25⁺ Tregs after the POI model was established. Sex hormone levels, follicle numbers, apoptotic events, and the Akt/FOXO3a signaling pathway molecules in the ovaries were assessed. Compared with control group, the weight of ovaries in both pZP3 group and pZP3‐Treg group was decreased and no difference was found between them. The number of follicles in the Treg transferred mice, like in pZP3 group, was significantly reduced compared to the control group, but showed a modest improvement when compared the pZP3 group alone. Significantly lower serum concentrations of follicle‐stimulating hormone, luteinizing hormone, and anti‐zona pellucida antibodies (AZPAbs) were found, while the concentrations of estradiol and anti‐Mullerian hormone increased. In mechanism, Treg cell transfer to ZP3 treated mice restored the levels of Caspase3 to control levels, and partially restored Bax, however, had no effect on Bcl‐2. Moreover, Treg cell transfer to ZP3 treated mice partially restored the levels of Akt and FOXO3a, and partially restored the ratios of p‐Akt/Akt and p‐FOXO3a/FOXO3a. In conclusion, Treg cells improved some aspects of ZP3‐induced POI which may be mediate by suppressing ovarian cells apoptosis and involving the Akt/FOXO3a signaling pathway. Therefore, Treg cells may be protective against autoimmune POI.