Inhibitory Effect of Sulfated Polysaccharide from Codium edule P.C. Silva Against 2,4-Dinitrofluorobenzene (DNFB)- Induced Allergic Contact Dermatitis on Female BALB/c Mice.

Purpose: Sulfated polysaccharide from Codium species has been reported for its antiinflammatoryactivities. However, the effect of sulfated polysaccharide from Codium edule on allergic responses has not been studied. The study was conducted to determine the effect ofsulfated polysaccharide (F1) from C. edule on allergic contact dermatitis (ACD) induced by2,4-dinitrofluorobenzene (DNFB) in female BALB/c mice. Methods: F1 was isolated using DEAE sepharose gel chromatography and chemically identifiedby LC-MS analyses. The effects of F1 on changes in ear thickness, allergic responses, andhistology were evaluated. The effects of F1 on the production of inflammatory cytokinesinterferon gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-ɑ) in serum were also quantifiedand compared with standard prednisolone therapy. Results: F1 was identified as a heteropolysaccharide with ß-D-galactans and ß-L-arabinans units.F1 was non-toxic at 2000 mg/kg. Administration of F1 in DNFB-challenged mice significantlysuppressed the increase in ear thickness, erythema, desquamation, and proliferation ofinflammatory cells. F1 significantly decreased the production of inflammatory markers, IFN-γand TNF-α in a dose-dependent manner when compared to the untreated group (P < 0.05). Conclusion: Results suggest that F1 from C. edule is a bioactive sulfated heteropolysaccharidewith anti-inflammatory activity and might be a valuable candidate molecule for the treatmentof allergic diseases such as ACD.

Enhanced Oral Bioavailability of the Pharmacologically Active Lignin Magnolol via Zr-Based Metal Organic Framework Impregnation.

Bioavailability plays an important role in drug activity in the human body, as certain drug amounts should be present to elicit activity. However, low bioavailability of drugs leads to negligible use for human benefit. In this study, the diversely active neolignan, magnolol, was impregnated onto a Zr-based organometallic framework [Uio-66(Zr)] to increase its low bioavailability (4-5%) and to test its potential acute oral toxicity. Synthesis of Uio-66(Zr) was done through the solvothermal method while simple impregnation at different time points was used to incorporate magnolol. The loading capacity of Uio-66(Zr) at 36 h was found to be significantly higher at 72.16 ± 2.15% magnolol than in other incubation time. Based on the OECD 425 (limit test), toxicity was not observed at 2000 mg kg-1 dose of mag@Uio-66(Zr) in female Sprague Dawley rats. The area under the curve (AUC) at 0-720 min of mag@Uio-66(Zr) was significantly higher than the AUC of free magnolol. Moreover, relative bioavailability increased almost two-folds using Uio-66(Zr). Unconjugated magnolol was found in the liver, kidney, and brain of rats in all treatment groups. Collectively, Uio-66(Zr) provided a higher magnolol bioavailability when used as drug carrier. Thus, utilization of Uio-66(Zr) as drug carrier is of importance for maximal use for poorly soluble and lowly bioavailable drugs.

ß-secretase 1 inhibitory activity and AMP-activated protein kinase activation of Callyspongia samarensis extracts.

The methanolic extract of Callyspongia samarensis (MCS) significantly inhibited ß-secretase 1 (IC50 99.82 µg/mL) in a dose-dependent manner and demonstrated a noncompetitive type of inhibition. Furthermore, it exhibited the highest AMPK activation (EC50 14.47 µg/mL) as compared with the standard, Aspirin (EC50 >100 µg/mL). HPLC/ESI-MS analysis of MCS extract revealed 15 peaks, in which nine peaks demonstrated similar fragmentation pattern with the known compounds in literature and in database library: 5-aminopentanoic acid (1), 4-aminobutanoic acid (3), Luotonin A (4), (E)-3-(1H-imidazol-5-yl) prop-2-enoic acid (8), Galactosphingosine (10), D-sphingosine (11), 5,7,4'-trihydroxy-3',5'-dimethoxyflavone (12), hydroxydihydrovolide (13), and 3,5-dibromo-4-methoxyphenylpyruvic acid (14); and 6 peaks are not identified (2, 5-7, 9, and 15). Acute oral toxicity test of MCS extract revealed that it is nontoxic, with an LD50 of >2000 mg/kg. Assessment of BBB permeability of MCS extract showed that compound 15 was able to cross the BBB making it a suitable candidate for developing CNS drugs.

Anti-angiogenic activity of Gracilaria coronopifolia J.G. Agardh extract by lowering the levels of trace metals (iron, zinc and copper) in duck chorioallantoic membrane and in vitro activation of AMP-kinase.

AMP-activated protein kinase (AMPK) is an intracellular energy sensor important in metabolic regulation, cell growth, and survival. However, the specific role of AMPK signaling pathway in the inhibition of angiogenesis remains unclear. The study highlights the activity on AMP activated protein kinase signaling pathways of a marine algae, Gracilaria coronopifolia, and its effects on angiogenesis. It was found that the most potent extract, GCD, inhibited angiogenesis significantly in the duck chorioallantoic membrane assay and also activated the enzyme AMP-kinase, in vitro. The dichloromethane extract was found most active in inhibiting angiogenesis in the duck chorioallantoic membrane (IC50 = 1.21 µg/mL) followed by GCH (IC50 = 3.08 µg/mL) (p = 0.479) and GCM (IC50 = 8.93 µg/mL) (p = 0.042). Benferroni post hoc analysis revealed that there was no significant difference between the percent inhibitions of GCH and GCM extracts (p = 0.479). Consequently, angiogenic inhibition caused lowering of iron, zinc, and copper levels in the duck CAM. Thin layer chromatography and gas chromatography-mass spectrometry revealed the components of each extracts. Notably, this is the first report on the kinase activity of a red algae G. coronopifolia extracts and a colorimetric-based quantification of angiogenesis based on metal content of CAM. Our data also suggest a novel therapeutic approach for inhibiting angiogenesis through the AMPK pathway.

In vitro angiotensin I converting enzyme inhibition by a peptide isolated from Chiropsalmus quadrigatus Haeckel (box jellyfish) venom hydrolysate.

The anti-angiotensin I converting enzyme activity of box jellyfish, Chiropsalmus quadrigatus Haeckel venom hydrolysate was studied. The venom extract was obtained by centrifugation and ultrasonication. Protein concentration of 12.99 µg/mL was determined using Bradford assay. The pepsin and papain hydrolysate was tested for its toxicity by Limit test following the OECD Guideline 425 using 5 female Sprague-Dawley rats. Results showed that the hydrolysate is nontoxic with an LD50 above 2000 mg/kg. In vitro angiotensin I converting enzyme (ACE) inhibitory activity was determined using ACE kit-WST. Isolation of ACE inhibitory peptides using column chromatography with SP-Sephadex G-25 yielded 8 pooled fractions with fraction 3 (86.5%) exhibiting the highest activity. This was followed by reverse phase - high performance liquid chromatography (RP-HPLC) with an octadecyl silica column (Inertsil ODS-3) using methanol:water 15:85 at a flow rate of 1.0 mL/min. Among the 13 fractions separated with the RP-HPLC, fraction 3.5 exhibited the highest ACE inhibitory activity (84.1%). The peptide sequence ACPGPNPGRP (IC50 2.03 µM) from fraction 3.5 was identified using Matrix-assisted laser desorption/ionization with time-of-flight tandem mass spectroscopy analysis (MALDI-TOF/MS).