A neutral heteropolysaccharide from Halenia elliptica D. Don: Extraction, structural characterization, antioxidant and antiaging activities.

Halenia elliptica D. Don (H. elliptica), which is also known as "heijicao" and "luanehuamao" in China, is recognised as a valuable Tibetan medicinal plant with polysaccharides as the main active ingredient. However, studies on the polysaccharides isolated from H. elliptica are few. A polysaccharide (HEPN-1) with a molecular weight of 10.80 kDa was mainly composed of Gal, Ara, Man, Glc, Rha and Fuc in a molar ratio of 25.56:24.52:4.58:3.37:2.62:1.00. Structural analysis showed that HEPN-1 had a backbone mainly consisting of 4-ß-Galp, 3,6-ß-Galp and 3,4,6-ß-Galp and branched chains that contained two arabinan (R1 and R2) and two heteropolysaccharide (R3 and R4) side chains. The branching degree of HEPN-1 was 0.52. Within the range of doses (75-300 µg/mL), HEPN-1 increased the enzyme activity of SOD, CAT and GSH-Px and decreased the MDA level in H2O2-induced RAW 264.7 cells in a dose-dependent manner. After 6 weeks of intragastric administration, 300 mg/kg HEPN-1 considerably improved the learning and memory deficits in mice and the antioxidant enzyme system. Moreover, the MDA formation in D-gal-induced aging mice was inhibited, possibly partly via the activation of the PI3K/Akt and Nrf2/HO-1 signalling pathways. Therefore, HEPN-1 could serve as a potential natural antioxidant to prevent aging.

Structural characteristics of mixed pectin from ginseng berry and its anti-obesity effects by regulating the intestinal flora.

Ginseng berry is the mature berry of ginseng and its polysaccharide has hypolipidaemic effect, but its mechanism remains unclear. A pectin (GBPA) with a molecular weight of 3.53 × 104 Da was isolated from ginseng berry, it was mainly composed of Rha (25.54 %), GalA (34.21 %), Gal (14.09 %) and Ara (16.25 %). Structural analysis showed that GBPA is a mixed pectin containing rhamnogalacturonan-I and homogalacturonan domains and has a triple helix structure. GBPA distinctly improved lipid disorders in obese rats, and changed intestinal flora with enrichments of Akkermansia, Bifidobacterium, Bacteroides and Prevotella, improved the levels of acetic acid, propionic acid, butyric acid and valeric acid. Serum metabolites which involved in the lipid regulation-related pathway, including cinnzeylanine, 10-Hydroxy-8-nor-2-fenchanone glucoside, armillaribin, 24-Propylcholestan-3-ol, were also greatly changed after GBPA treatment. GBPA activated AMP-activated protein kinase, phosphorylated acetyl-CoA carboxylase, and reduced the expression of lipid synthesis-related genes sterol regulatory element-binding protein-1c and fatty acid synthases. The regulatory effects of GBPA on lipid disorders in obese rats are related to the regulation of intestinal flora and activation of AMP-activated protein kinase pathway. Ginseng berry pectin could be considered in the future as a health food or medicine to prevent obesity.

A machine learning cardiac magnetic resonance approach to extract disease features and automate pulmonary arterial hypertension diagnosis.

AIMS: Pulmonary arterial hypertension (PAH) is a progressive condition with high mortality. Quantitative cardiovascular magnetic resonance (CMR) imaging metrics in PAH target individual cardiac structures and have diagnostic and prognostic utility but are challenging to acquire. The primary aim of this study was to develop and test a tensor-based machine learning approach to holistically identify diagnostic features in PAH using CMR, and secondarily, visualize and interpret key discriminative features associated with PAH. METHODS AND RESULTS: Consecutive treatment naive patients with PAH or no evidence of pulmonary hypertension (PH), undergoing CMR and right heart catheterization within 48 h, were identified from the ASPIRE registry. A tensor-based machine learning approach, multilinear subspace learning, was developed and the diagnostic accuracy of this approach was compared with standard CMR measurements. Two hundred and twenty patients were identified: 150 with PAH and 70 with no PH. The diagnostic accuracy of the approach was high as assessed by area under the curve at receiver operating characteristic analysis (P < 0.001): 0.92 for PAH, slightly higher than standard CMR metrics. Moreover, establishing the diagnosis using the approach was less time-consuming, being achieved within 10 s. Learnt features were visualized in feature maps with correspondence to cardiac phases, confirming known and also identifying potentially new diagnostic features in PAH. CONCLUSION: A tensor-based machine learning approach has been developed and applied to CMR. High diagnostic accuracy has been shown for PAH diagnosis and new learnt features were visualized with diagnostic potential.

Metformin Prevents Follicular Atresia in Aging Laying Chickens through Activation of PI3K/AKT and Calcium Signaling Pathways.

Increased follicular atresia occurs with aging and results in reduced fecundity in laying chickens. Therefore, relieving follicular atresia of aging poultry is a crucial measure to maintain sustained high laying performance. As an antiaging agent, metformin was reported to play important roles in preventing aging in diverse animals. In this study, the physiological state of the prehierarchical follicles in the peak-laying hens (D280) and aged hens (D580) was compared, followed with exploration for the possible capacity of metformin in delaying atresia of the prehierarchical follicles in the aged D580 hens. Results showed that the capacity of yolk deposition within follicles declined with aging, and the point of endoplasmic reticulum- (ER-) mitochondrion contact decreased in the ultrastructure of the follicular cells. Meanwhile, the expression of apoptosis signaling genes was increased in the atretic small white follicles. Subsequently, the H2O2-induced follicular atresia model was established to evaluate the enhancing capacity of metformin on yolk deposition and inhibition of apoptosis in the atretic small white follicles. Metformin inhibited apoptosis through regulating cooperation of the mitochondrion-associated ER membranes and the insulin (PI3K/AKT) signaling pathway. Furthermore, metformin regulated calcium ion homeostasis to relieve ER-stress and inhibited release of mitochondrion apoptosis factors (BAD and caspase). Additionally, metformin activated PI3K/AKT that suppressed activation of BAD (downstream of the insulin signaling pathway) in the atretic follicles. Further, serum estrogen level and liver estrogen receptor-α expression were increased after dietary metformin supplementation in D580 hens. These results indicated that administration of dietary metformin activated the PI3K/AKT and calcium signaling pathway and enhanced yolk deposition to prevent chicken follicular atresia.

Improvement of eggshell quality by dietary N-carbamylglutamate supplementation in laying chickens.

Egg quality defects seriously reduce the quality grade and increase egg breakage in egg marketing activities. In this study, the effect of N-carbamylglutamate (NCG) on eggshell quality was investigated by evaluating calcium absorption and calcification in laying hens. A total of 30 newly hatched female Hy-Line chicks were randomly assigned to the control group (basal diet) and treatment group (basal diet supplemented with 1% NCG). At 25 wk, eggs from each group were obtained to assess egg quality parameters. Blood samples were collected for analysis of mineral, hormone, and amino acids levels at 16 h after laying egg. Uterine tissues were removed and fixed in 4% neutral paraformaldehyde solution or kept in liquid nitrogen for mineral determination, quantitative PCR, and Western blot. Results showed that the egg quality (eggshell thickness, strength and percentage, egg specific gravity, and eggshell effective thickness) was significantly increased while effective thickness of mastoid layer, width of mastoid gap, and mammillary knobs were significantly decreased by dietary NCG supplementation (P < 0.05). The levels of minerals (Ca, P, Fe, Mg, Na, K) in eggshell, plasma, and uterus were remarkably elevated (P < 0.05). Meanwhile, the concentrations of calcium metabolism-related hormones (17ß-estradiol, parathyroid hormone, and calcitonin) were increased in the NCG group (P < 0.05). Moreover, expression of calbindin 1, carbonic anhydrase 2, ovalbumin, ovotransferrin, ovocleidin-17, ovocleidin-116, and clusterin mRNAs, as well as calbindin 1 and ATP2A1 proteins in uterus, duodenum, and kidney, was all upregulated in hens fed with NCG (P < 0.05). In addition, the number of blood vessels in the uterus, height of uterine mucosal folds, villus length in endometrium, and areas of uterine mucosal folds were significantly increased in the NCG group (P < 0.05). In conclusion, dietary 1% NCG supplementation during 0 to 25 wk can improve eggshell quality through changes in endometrial morphology, expression of calcium metabolism-related genes, and secretion of related hormones to promote eggshell formation in the laying hens.

Effect of dietary N-carbamylglutamate on development of ovarian follicles via enhanced angiogenesis in the chicken.

N-carbamylglutamate (NCG), an analogue of N-acetyl-L-glutamate (NAG), can increase arginine synthesis in mammals and improve the reproductive performance. However, the effect of NCG on poultry laying performance is still unclear. This study investigated the effect of dietary NCG on development of chicken ovarian follicles. The dosage and timing for NCG administration were evaluated for its effect on follicular development. Results showed that supplementation with 1% NCG in the diet for 14 D led to accelerated development of growing follicles (over 60 µm in oocyte diameter) and significantly increased feed intake and feed efficiency. Plasma amino acids (AA) analysis showed that feeding with 1% NCG significantly increased of plasma AA levels. RNA-seq analysis revealed that NCG supplementation upregulated expression of genes related to angiogenesis and cell proliferation, but downregulated expression of apoptosis-related genes. Meanwhile, RT-qPCR and Western blot analysis validated the RNA-seq results. Moreover, NCG enhanced plasma NO level; upregulated expression of PKG-I, Raf1, and p-p38; and increased angiogenesis of the ovaries. In conclusion, dietary NCG (1% for 14 D) can promote development of ovarian follicles by increasing angiogenesis in ovaries of the chicken.

Structure-Based Design and Discovery of a Long-Acting Cocaine Hydrolase Mutant with Improved Binding Affinity to Neonatal Fc Receptor for Treatment of Cocaine Abuse.

Despite decades of efforts to develop a pharmacotherapy for cocaine abuse treatment, there is still no FDA-approved treatment of diseases associated with this commonly abused drug. Our previously designed highly efficient cocaine hydrolases (CocHs) and the corresponding Fc-fusion proteins (e.g., CocH3-Fc) are recognized as potentially promising therapeutic enzyme candidates for cocaine abuse treatment, but all with limited biological half-lives. In order to prolong the biological half-life and, thus, decrease the required frequency of the enzyme administration for cocaine abuse treatment, we have modeled the Fc-fusion CocH binding with neonatal Fc receptor (FcRn) in the present study. This approach led to the design and testing of CocH3-Fc(M6), a CocH3-Fc mutant with nearly 100-fold increased binding affinity: from Kd = ~ 4 µM to Kd = 43 nM. As a result, CocH3-Fc(M6) indeed revealed a markedly prolonged biological half-life (t1/2 = 206 ± 7 h or ~ 9 days) in rats, longer than other known Fc-fusion protein drugs such as abatacept and alefacept (for other therapeutic purposes) in the same species (rats). It has been demonstrated that a single dose of 3 mg/kg CocH3-Fc(M6) effectively blocked 20 mg/kg cocaine-induced hyperactivity on day 18 after CocH3-Fc(M6) administration. This is the first attempt to rationally design long-acting Fc-fusion enzyme mutant based on combined computational modeling and experimental measurement of the Fc-fusion CocH binding with FcRn. The similar structure-based design strategy may be used to prolong the biological half-lives of other Fc-fusion protein drugs.

Is there a future for andrographolide to be an anti-inflammatory drug? Deciphering its major mechanisms of action.

Andrographis paniculata has long been part of the traditional herbal medicine system in Asia and in Scandinavia. Andrographolide was isolated as a major bioactive constituent of A. paniculata in 1951, and since 1984, andrographolide and its analogs have been scrutinized with modern drug discovery approach for anti-inflammatory properties. With this accumulated wealth of pre-clinical data, it is imperative to review and consolidate different sources of information, to decipher the major anti-inflammatory mechanisms of action in inflammatory diseases, and to provide direction for future studies. Andrographolide and its analogs have been shown to provide anti-inflammatory benefits in a variety of inflammatory disease models. Among the diverse signaling pathways investigated, inhibition of NF-κB activity is the prevailing anti-inflammatory mechanism elicited by andrographolide. There is also increasing evidence supporting endogenous antioxidant defense enhancement by andrographolide through Nrf2 activation. However, the exact pathway leading to NF-κB and Nrf2 activation by andrographolide has yet to be elucidated. Validation and consensus on the major mechanistic actions of andrographolide in different inflammatory conditions are required before translating current findings into clinical settings. There are a few clinical trials conducted using andrographolide in fixed combination formulation which have shown anti-inflammatory benefits and good safety profile. A concerted effort is definitely needed to identify potent andrographolide lead compounds with improved pharmacokinetics and toxicological properties. Taken together, andrographolide and its analogs have great potential to be the next new class of anti-inflammatory agents, and more andrographolide molecules are likely moving towards clinical study stage in the near future.

[Effect of oxygen therapy on the morphology of cardiac muscle, lung and liver in rats with acute hydrogen sulfide intoxication].

OBJECTIVE: To evaluate the effects of different oxygen therapy technique (different concentrations of normobaric oxygen and the hyperbaric oxygen) on the ultrastructure of cardiac muscle, lung and liver in rats with acute hydrogen sulfide intoxication. METHODS: One hundred healthy male Wistar rats were randomly divided into five groups: normal control group (A), poisoned group (B), oxygen therapy group (C), oxygen therapy group (D) and oxygen therapy group (E). After the exposure to 300 ppm H2S for 60 min in a static exposure tank (1 m3), the rats were treated with oxygen therapy, C, D and E groups were given 33% oxygen, 50% oxygen of atmospheric oxygen and hyperbaric oxygen therapy for 100 min, respectively. The rats in normal control group inhaled air under the same environment. After exposure and therapy, the tissues of lung, heart and liver were observed under light microscope and electron microscope. RESULTS: The results of light microscope examination showed that the broken and not well aligned cardiac myofilaments, cytoplasmic edema and pyknosis could be seen in group B. The well aligned and clear cardiac myofilaments appeared in group C, D and E. The alveolar hemorrhage, edema and inflammatory cells exudation could not be seen in group A. Alveolar epithelial cell edema, unsmooth alveolar edge and alveolar inflammatory cells exudation could be found in group B. The unsmooth alveolar septal borders and pulmonary edema could be seen occasionally in group C and D, the alveolar inflammatory cells exudation could not be seen in group E. The regular hepatic boards and the uniform hepatic cellular nuclei were found in group A. The disordered hepatic boards, widened cellular gaps and cytoplasmic edema could be seen occasionally in group B. The irregular hepatic boards and ballooning degeneration could be seen in group C and D. The regular hepatic boards and uniform cytoplasm could be found in group E. The results of electron microscope examination indicated that the mitochondrial swelling, autolyzing, fuzzy and breakage of myocardial cells were observed in group B; the clear mitochondrial structure appeared in group E. The apoptosis and organelle vacuole of alveolar epithelial cells could be observed in group B. The relatively normal nuclei of alveolar epithelial cells could be seen in group E. The lax cytoplast structure of hepatocytes, unclear nuclear membrane, lumped chromatin, slightly swelled mitochondria and phagosomes were observed in group B. However, no improved change was observed in group C, D and E. CONCLUSION: Hydrogen sulfide could induce the extensive and severe damage of myocardial mitochondria, alveolar epithelial cells and hepatocytes, the oxygen therapy in good time could reduce significantly the myocardial injury, and improve the lung injury to some extent. High-pressure oxygen therapy is better than the normobaric oxygen therapy.

[Evaluating the effects of different oxygen therapies on the rats with acute nitrogen asphyxia].

OBJECTIVE: To Evaluate the effects of different oxygen therapies on the rats with acute nitrogen asphyxia and to study the best oxygen therapic protocol for patients with acute nitrogen asphyxia on the spot. METHODS: Sixty healthy male Wistar rats were divided into 5 groups: control, exposure to nitrogen, 33% oxygen treatment, 50% oxygen treatment and hyperbaric oxygen treatment groups. The behavioral performance, arterial oxygen pressure (PO2), carbon dioxide partial pressure (PCO2) and oxygen saturation (SPO2), biochemical changes in liver and kidney function and myocardial enzymes in 5 groups were measured. RESULTS: The rats exposed to nitrogen firstly were excited then inactive symptoms, but consciousness was recovered after oxygen therapy. The PO2 and SPO2 in nitrogen exposure group were (79.67 +/- 9.12) and (94.92 +/- 2.78) mm Hg, respectively, which were significantly lower than those in control group (P<0.01). The PO2 and SPO2 of 3 oxygen treatment groups were (94.75 +/- 7.24), (94.92 +/- 8.98), (104.58 +/- 7.12)mm Hg and (97.17 +/- 0.83), (96.92 +/- 1.16), (97.42 +/- 0.67)mm Hg, respectively, which were significantly higher than those in nitrogen exposure group (P<0.05). The PO2 in hyperbaric oxygen treatment group was significantly higher than those in other 2 oxygen treatment groups (P<0.05). The SPO2 in hyperbaric oxygen treatment group was (51.42 +/- 6.60) mm Hg which was significantly higher than that [(44.58 +/- 3.42)mm Hg] in 50% oxygen treatment groups (P< 0.05). AST [(270.50 +/- 49.05 )U/L], ALT [(122.67 +/- 55.44 )U/L], BUN [(7.31 +/- 0.93 )mmol/L], Cr[(28.32 +/- 4.35) micromol/L], CK [(1808.42 +/- 582.05)U/L] and CtnI [(22.52 +/- 14.29 )ng/ml] in nitrogen exposure group were significantly higher than those in control group (P<0.05). AST [(165.25 +/- 30.87) U/L], HBDH [(350.83 +/- 103.00)U/L] and CtnI [(11.23 +/- 5.38) ng/ml] in hyperbaric oxygen treatment group were significantly lower than those in other 2 oxygen treatment groups (P<0.05). CONCLUSION: Timely and effective oxygen therapy can significantly increase arterial pressure of oxygen and oxygen saturation in the rats with acute nitrogen asphyxia, and can improve liver function and cardiac damage. The hyperbaric oxygen chamber can significantly increase the therapeutic effects on rats with acute nitrogen asphyxiation.

[Evaluation of different oxygen therapies on therapeutic effects in rats with acute carbon dioxide poisoning].

OBJECTIVE: To study therapeutic effects by using different oxygen therapies in rats with acute carbon dioxide poisoning, to select the best oxygen therapy technology for patients with acute carbon dioxide poisoning on the spot. METHODS: Sixty healthy male Sprague-Dawley rats were randomized into normal control group, carbon dioxide exposure group, hyperbaric oxygen treatment group (pressure 2 ATA, FiO(2)100%), high concentration of atmospheric oxygen treatment group (FiO(2)50%), low concentration of atmospheric oxygen treatment group (FiO(2)33%). After treated with different oxygen in rats with acute carbon dioxide poisoning, arterial pH, PO2 and PCO2 of rats were detected, in addition observe pathological changes of lung tissue and brain tissue. RESULTS: The arterial pH (7.31 ± 0.06) and PO2 [(68.50 ± 15.02) mm Hg] of carbon dioxide exposure group were lower than those of control group [pH (7.42 ± 0.02) and PO2 (92.83 ± 8.27) mm Hg], PCO2 [(71.66 ± 12.10) mm Hg] was higher than that of control group [(48.25 ± 2.59) mm Hg] (P < 0.05); the arterial pH (hyperbaric oxygen treatment group 7.37 ± 0.02, high concentration of atmospheric oxygen treatment group 7.39 ± 0.03, low concentration of atmospheric oxygen treatment group 7.38 ± 0.02) and PO2 of oxygen treatment groups [hyperbaric oxygen treatment group, high concentration of atmospheric oxygen treatment group, low concentration of atmospheric oxygen treatment group were (82.25 ± 12.98), (84.75 ± 11.24), (83.75 ± 16.77) mm Hg, respectively] were higher than that of carbon dioxide exposure group, PCO2 [hyperbaric oxygen treatment group, high concentration of atmospheric oxygen treatment group, low concentration of atmospheric oxygen treatment group were (52.25 ± 4.95), (51.75 ± 4.82), (52.66 ± 5.61) mm Hg, respectively] was lower than that of carbon dioxide exposure group (P < 0.05); there was no significant difference of the arterial pH, PO2 and PCO2 between oxygen treatment groups and control group (P > 0.05); there was no significant difference of the arterial pH, PO2 and PCO2 among oxygen treatment groups (P > 0.05). There was large area of bleeding of lungs in rats with carbon dioxide poisoning, the bleeding of lungs in rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment was better than the rats with carbon dioxide poisoning, there was no abnormal appearance of lungs in rats with hyperbaric oxygen treatment. The light microscope observation showed that there were diffuse bleeding and exudation of lungs in rats with carbon dioxide poisoning, the bleeding and exudation of lungs in rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment were better than the rats with carbon dioxide poisoning, there were only minor bleeding and exudation of lungs in rats with hyperbaric oxygen treatment. There was no difference of brain in anatomy and microscopy among all groups, there were no significant bleeding, edema, cell degeneration and necrosis. CONCLUSIONS: Lung pathology in acute carbon dioxide poisoning rats with hyperbaric oxygen treatment is better than the rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment, there is no significant difference of effect between high concentration of atmospheric oxygen treatment group and low concentration of atmospheric oxygen treatment group, however, the results of blood gas analysis and lung pathology than the exposure group improved, so qualified medical unit for hyperbaric oxygen therapy as soon as possible, hyperbaric oxygen treatment facilities in the absence of circumstances, the emergency treatment of early oxygen is also a good measure.