Identification of key sensory and chemical factors determining flavor quality of Xinyu mandarin during ripening and storage.

Xinyu mandarin is popular for its good flavor, but its flavor deteriorates during postharvest storage. To better understand the underlying basis of this change, the dynamics of the sensory profiles were investigated throughout fruit ripening and storage. Sweetness and sourness, determined especially by sucrose and citric acid content, were identified as the key sensory factors in flavor establishment during ripening, but not in flavor deterioration during storage. Postharvest flavor deterioration is mainly attributed to the reduction of retronasal aroma and the development of off-flavor. Furthermore, sugars, acids and volatile compounds were analyzed. Among the 101 detected volatile compounds, 10 changed significantly during the ripening process. The concentrations of 15 volatile components decreased during late postharvest storage, among which α-pinene and d-limonene were likely to play key roles in the reduction of aroma. Three volatile compounds were found to increase during storage, associated with off-flavor development.

Nifurtimox Hampered the Progression of Astroglioma In vivo Via Manipulating the AKT-GSK3ß axis.

BACKGROUND: Astroglioma, one major form of brain tumors, has remained principally tough to handle for decades, due to the complexity of tumor pathology and the poor response to chemo- and radio-therapies. METHODS: Our previous study demonstrated that nifurtimox could regulate the signaling axis of AKT-GSK3ß in various tumor types including the astroglioma U251 cells. Intriguingly, earlier case studies suggested that nifurtimox could possibly permeate the blood brain barrier and arrest neuroblastoma in the brain. These observations jointly encouraged us to explore whether nifurtimox would hinder the growth of astroglioma in vivo. RESULTS: Our results exhibited that nifurtimox could competently hinder the development of astroglioma in the mouse brain as compared to temozolomide, the first line of drug for brain tumors. Meanwhile the surviving rate, as well as the body-weight was dramatically upregulated upon nifurtimox treatment, as compared to that of temozolomide. These findings offered nifurtimox as a better alternative drug in treating astroglioma in vivo. CONCLUSION: Persistently, the manipulation of the signaling axis of AKT-GSK3ß in astroglioma was found in line with earlier findings in neuroblastoma when treated with nifurtimox.

An Overview of Available Antimalarials: Discovery, Mode of Action and Drug Resistance.

Malaria is one of the three most deadly infectious diseases in the world and seriously endangers human health and life. To reduce the public health burden of this disease, scientists have focused on the discovery and development of effective antimalarial drugs, from quinine and chloroquine to antifolates and artemisinin and its derivatives, which all play a profound role in the treatment of malaria. However, drugresistant strains of Plasmodium falciparum have emerged due to frequent use of antimalarials and have become increasingly resistant to existing antimalarial drugs, causing disastrous consequences in the world. In particular, artemisinin resistance is of greatest concern which was reported in 2008. Resistance to artenisinins has been a major obstacle for malaria control, and current efforts to curb artemisinin resistance have not been successful. Based on the current situation, it is urgent to develop more effective new antimalarials with distinct targets from conventional antimalarials in the world, which could facilitate to minimize the phenomenon of drug resistance. This review aims to summarize different kinds of antimalarial therapeutic efficacy, mechanisms of action and resistance, and proposes new solutions aiming towards further improvement of malaria elimination.

Effect of Pb Exposure on Synaptic Scaling Through Regulation of AMPA Receptor Surface Trafficking.

Homeostatic synaptic plasticity (HSP) helps to stabilize the neuronal network activity, which is essential for optimal information coding. Synaptic scaling is a form of homeostatic plasticity that stabilizes neuronal firing in response to activity blockade. Lead (Pb) is a ubiquitous environmental neuro-toxicant and can impair the input-specific Hebbian type synaptic plasticity, but whether Pb exerts effects in HSP remains unknown. We previously reported that blocking L-type calcium channel induces synaptic scaling, which stimulates the synthesis of all-trans retinoic acid (RA) and the expression of GluA2-lacking α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor. Given Pb is a potent blocker of calcium channel, we hypothesized Pb may participate in synaptic scaling accompanied by RA synthesis and AMPA receptor trafficking. In this study, cultured hippocampal neurons were treated with Pb (1 µM 5 min, 15 min, 4 h, 24 h, and 10 µM 24 h) alone or in combination with tetrodotoxin (TTX, 1 µM, 24 h). The results showed that Pb alone, either at 1 µM or 10 µM, cannot induce synaptic scaling. But Pb participated in synaptic scaling when concurrent with TTX (10 µM Pb + 1 µM TTX, 24 h). Further results showed that surface heteromeric GluA1 and GluA2 AMPA receptors were increased in TTX+ Pb-induced synaptic scaling. In addition, RA was proved not to participate in TTX+ Pb-mediated synaptic scaling. Taken together, our work supported that TTX+ Pb could induce synaptic scaling and enhance synaptic accumulation of AMPAR GluA1 and GluA2 during synaptic up scaling. Our study would help for elucidation of the Pb-induced neuronal network instability mechanism.

Fructus Ligustri Lucidi modulates estrogen receptor expression with no uterotrophic effect in ovariectomized rats.

BACKGROUND: Accumulating evidence suggests that Fructus Ligustri Lucidi (FLL) plays a beneficial role in preventing the development of osteoporosis. However, the effects of FLL on estrogen receptor (ER) α and ERß expressions remain unknown. Therefore, in the current study we attempted to probe into the effects of FLL on ERα and ERß expressions in femurs, tibias and uteri of ovariectomized (OVX) rats. METHODS: The OVX rats were orally administrated with FLL water extract (3.5 g/kg/day) for 12 weeks. The uteri, femurs, tibias and serum were harvested from rats. The serum levels of estrogen (E2), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were determined by ELISA. The expressions of ERα and ERß in the femurs and tibias as well as uteri were analysed by western blot and immunohistochemical staining. RESULTS: FLL treatment did not increase uterus relative weight in OVX rats. Further, FLL treatment increased ERα expression in the femurs and tibias, and enhanced ERß expression in the uteri of OVX rats. However, the resulted expression of ERα was stronger than that of ERß in OVX rats in response to FLL treatment. Meanwhile, administration with FLL to OVX rats increased FSH and LH but did not increase E2 level in the serum. CONCLUSION: FLL treatment shows tissue selection on ERα and ERß expressions in the femurs and tibias as well as uteri of OVX rats without uterotrophic effect, which may offer the scientific evidence of the efficiency and safety of its clinical application.

Kinetics and pathways of Bezafibrate degradation in UV/chlorine process.

UV/chlorine, as a novel disinfection method, has attracted great interest due to its effective removal for pathogenic microorganism and degradation of trace organic contaminants existed in water environment. This paper investigated the degradation kinetics and pathways of Bezafibrate (BZF), a typical antilipemic drug, during UV/chlorine process. The results showed that 92.3% of BZF was degraded after 20 min in UV/chlorine process. This indicated HO• and reactive chlorine species (RCSs) formed in UV/chlorine played the dominant role in degrading BZF. Observed rate constants of BZF degradation (k obs,BZF) in UV/chlorine process increased linearly in a wide chlorine dosage from 0.1 to 1.0 mM, which implied that ClO• generated from the reactions of chlorine with HO• and Cl• could react with BZF rapidly. The steady-state kinetic modeling result proved this deduction and the rate constant of ClO• with BZF was fitted to be 5.0 × 108 M-1 s-1. k obs,BZF was affected by Cl- and HA. The total contribution of RCSs (including Cl•, Cl2•-, and ClO•) to the degradation of BZF was determined to be ~ 80%, which is much higher than that of HO•. Thirteen degradation products of BZF were identified by LC-MS/MS. Initial degradation products were arisen from hydroxylation, chlorine substitution and cyclization by HO• and RCSs, and then further oxidized to generate acylamino cleavage and demethylation products.

Curcumin treatment suppresses CCR7 expression and the differentiation and migration of human circulating fibrocytes.

BACKGROUND/AIM: Recent studies have demonstrated that circulating fibrocytes contribute to the formation and development of fibrosis. Curcumin, a polyphenolic compound isolated from turmeric, has been shown to have anti-fibrotic effects in various organs. We and others have demonstrated that curcumin beneficially affects the development of fibrosis. However the effect of curcumin on circulating fibrocytes has not been reported. METHODS: Human circulating fibrocytes were isolated from leukocyte concentrates of healthy human donors and identified based on the expression of CD34, CD45, collagen I (COLI), and chemokine receptor CCR7 (CCR7) via flow cytometry. Cell Counting Kit-8 was used to evaluate cell viability. The effect of curcumin on the differentiation and migration of human circulating fibrocytes was evaluated by immunofluorescence staining, flow cytometry and a transwell migration assay. Transforming growth factor (TGF)-ß1 secretion was examined by ELISA. RESULTS: Curcumin treatment (72 h; 20 µM) significantly decreased the expression of COL I, α-SMA and CCR7, as well as TGF-ßl secretion, in human circulating fibrocytes. The inhibitory effect of curcumin on the differentiation and migration of human circulating fibrocytes is likely via regulating the CCR7/CCL21 signaling pathway, in particular by reducing CCR7 expression. These observed effects may be beneficial in resolving fibrosis by suppressing TGF-ß1 secretion. CONCLUSION: Our results suggest that curcumin has the potential to suppress the differentiation and migration of circulating fibrocytes, which would provide new explanation for curcumin's application in the development of fibrosis in various organs.

Enhancement of flap survival and changes in angiogenic gene expression after AAV2-mediated VEGF gene transfer to rat ischemic flaps.

Necrosis of surgically transferred flaps due to ischemia is a serious wound problem. We evaluated the improvement of flap survival and changes in angiogenic gene expression profiles after transfer of the VEGF gene by means of adeno-associated virus type 2 (AAV2) vector to rat ischemic flaps. Thirty rats were divided into one experimental group, one AAV2-GFP group, and one saline group. AAV2-VEGF or AAV2-GFP were injected intradermally into the rat dorsum in the AAV2-VEGF or AAV2-GFP group. The saline group received saline injection. A 3 × 10 cm flap was raised in each rat two weeks post-injection. One week after surgery, flap viability was evaluated. Angiogenesis real-time PCR array was performed to analyze the expression of angiogenesis-associated genes. The AAV2-VEGF treatment significantly improved flap survival (p<0.05). Immunohistochemical staining showed increased VEGF expression in AAV2-VEGF treated flaps. The PCR array identified remarkable changes in 6 out of the 84 angiogenesis-associated genes in AAV2-VEGF treated flaps. Particularly, EGF, PDGF-A and VEGF-B genes were up-regulated in these flaps. In contrast, FGF2 gene expression was down-regulated. In conclusion, AAV2-VEGF improves flap survival and affects the expression of a series of endogenous growth factor genes, which likely play critical roles in the enhancement of ischemic flap survival.