Intravenous immunoglobulin for postpolio syndrome: a systematic review and meta-analysis.

BACKGROUND: Postpolio syndrome (PPS) is characterized by progressive disabilities that develop decades after prior paralytic poliomyelitis. Because chronic inflammation may be the process underlying the development of PPS, immunomodulatory management, such as intravenous immunoglobulin (IVIg) administration, may be beneficial. METHODS: We performed a systematic review and meta-analysis of published randomized controlled trials (RCTs) and prospective studies that evaluated the efficacy of IVIg in managing PPS. Electronic databases, including PubMed, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials, were searched for articles on PPS published before December 2014. The primary outcomes were pain severity, fatigue scores, and muscle strength. The secondary outcomes were physical performance, quality of life (QoL), and cytokine expression levels. RESULTS: We identified 3 RCTs involving 241 patients and 5 prospective studies involving 267 patients. The meta-analysis of pain severity (weighted mean difference [WMD] = -1.02, 95% confidence interval [CI] = -2.51 to 0.47), fatigue scores (WMD = 0.28, 95% CI -0.56 to 1.12), and muscle strength revealed no significant differences between the IVIg and the placebo group. Regarding QoL, the RCTs yielded controversial outcomes, with improvement in only certain domains of the Short Form 36 (SF-36). Moreover, one prospective study reported significant improvement on SF-36, particularly in patients aged younger than 65 years, those with paresis of the lower limbs, and high pain intensity. CONCLUSION: The present review indicated that IVIg is unlikely to produce significant improvements in pain, fatigue, or muscle strength. Thus, routinely administering IVIg to patients with PPS is not recommended based on RCTs. However, a potential effect in younger patients with lower limbs weakness and intense pain requires confirmation from further well-structured trials.

In silico and in vitro characterization of anti-amyloidogenic activity of vitamin K3 analogues for Alzheimer's disease.

BACKGROUND: Aggregation of amyloid-beta (Aß) has been proposed as the main cause of Alzheimer's disease (AD). Vitamin K deficiency has been linked to the pathogenesis of AD. Therefore, 15 synthesized vitamin K3 (VK3) analogues were studied for their anti-amyloidogenic activity. METHODS: Biological and spectroscopic assays were used to characterize the effect of VK3 analogues on amyloidogenic properties of Aß, such as aggregation, free radical formation, and cell viability. Molecular dynamics simulation was used to calculate the binding affinity and mode of VK3 analogue binding to Aß. RESULTS: Both numerical and experimental results showed that several VK3 analogues, including VK3-6, VK3-8, VK3-9, VK3-10, and VK3-224 could effectively inhibit Aß aggregation and conformational conversion. The calculated inhibition constants were in the µM range for VK3-10, VK3-6, and VK3-9 which was similar to the IC50 of curcumin. Cell viability assays indicated that VK3-9 could effectively reduce free radicals and had a protective effect on cytotoxicity induced by Aß. CONCLUSIONS: The results clearly demonstrated that VK3 analogues could effectively inhibit Aß aggregation and protect cells against Aß induced toxicity. Modified VK3 analogues can possibly be developed as effective anti-amyloidogenic drugs for the treatment of AD. GENERAL SIGNIFICANCE: VK3 analogues effectively inhibit Aß aggregation and are highly potent as anti-amyloidogenic drugs for therapeutic treatment of AD.

Euphorbia formosana root extract induces apoptosis by caspase-dependent cell death via Fas and mitochondrial pathway in THP-1 human leukemic cells.

Acute myeloid leukemia (AML), a very rare type of cancer, generally affects patients over 50 years old. While clinical drugs to treat advanced stages of AML exist, the disease becomes increasingly resistant to therapies. Euphorbia formosana Hayata (EF) is a native Taiwanese medicinal plant used to treat rheumatism, liver cirrhosis, herpes zoster, scabies, and photoaging, along with tumor suppression. However, the mechanisms by which it suppresses tumors have not been explored. Here, we provide molecular evidence that a hot-water extract of Euphorbia formosana (EFW) selectively inhibited the growth of human leukemic cancer cells more than other solid human cancer cell lines. Most importantly, the plant extract had limited toxicity toward healthy peripheral blood mononuclear cells (PBMCs). After THP-1 leukemic cells were treated with 50-100 µg/mL EFW for one day, the S phase DNA content of the cells increased, while treatment with 200-400 µg/mL caused the cells to accumulate in the G0/G1 phase. Notably, EFW did not affect A-549 lung cancer cells. The effectiveness of EFW against THP-1 cells may be through caspase-dependent apoptosis in leukemic cells, which is mediated through the Fas and mitochondrial pathways. The potent antileukemic activity of EFW in vitro warrants further investigation of this plant to treat leukemias and other malignancies.

Oroxylin-A rescues LPS-induced acute lung injury via regulation of NF-κB signaling pathway in rodents.

BACKGROUND AND PURPOSE: Successful drug treatment for sepsis-related acute lung injury (ALI) remains a major clinical problem. This study was designed to assess the beneficial effects of post-treatment of oroxylin A (OroA), a flavonoid, in ameliorating lipopolysaccharides (LPS)-induced lung inflammation and fatality. EXPERIMENTAL APPROACH: Rats were injected with LPS (10 mg/kg, iv) to induce ALI, and OroA was given (15 mg/kg, iv) 1 hr or 6 hrs after LPS challenge. Twenty four hrs after LPS challenge, biochemical changes in the blood and lung tissues, and morphological/histological alterations in the lung associated with inflammation and injury were examined. Therapeutic effect of OroA was assessed by measuring the survival rate in endotoxemic mice. KEY RESULTS: LPS (10 mg/kg, iv) significantly altered WBC counts, elevated plasma tumor necrosis factor (TNF)-α and nitric oxide (NO), increased pulmonary edema, thickened alveolar septa, and decreased survival rate. These changes were ameliorated by OroA (15 mg/kg, iv) administered 1 hr or 6 hrs after LPS challenge. This post-treatment also significantly attenuated LPS-induced activation of nuclear factor-κB (NF-κB) and the release of high mobility group box 1 (HMGB1) in lung tissues. Furthermore, post-treatment with OroA (60 mg/kg, ip) administered 1 hr or 6 hrs after LPS challenge in mice significantly increased survival rate. CONCLUSION AND IMPLICATION: OroA administered after induction of ALI by LPS significantly prevent and revere lung tissues injuries with increased survival rate. Positive post-treatment effects of OroA suggest that OroA is a potentially useful candidate for managing lung inflammation in LPS-induced endotoxemia and septic shock.

Hydrazone chelators for the treatment of iron overload disorders: iron coordination chemistry and biological activity.

The potentially tridentate ligand 2-pyridinecarbaldehyde isonicotinoyl hydrazone (HPCIH) and its analogues are an emerging class of orally effective Fe chelators that show great promise for the treatment of Fe overload diseases. Herein, we present an extensive study of the Fe coordination chemistry of the HPCIH analogues including the first crystallographically characterised Fe(II) complex of these chelators. Unlike most other clinically effective Fe chelators, the HPCIH analogues bind Fe(II) and not Fe(III). In fact, these chelators form low-spin bis-ligand Fe(II) complexes, although NMR suggests that the complexes are close to the high-spin/low-spin crossover. All the Fe complexes show a high potential Fe(III/II) redox couple (> 500 mV vs. NHE) and cyclic voltammetry in aqueous or mixed aqueous/organic solvents is irreversible as a consequence of a rapid hydration reaction that occurs upon oxidation. A number of the HPCIH analogues show high activity at inducing Fe efflux from cells and also at preventing Fe uptake by cells from the serum Fe transport protein transferrin. As a class of ligands, these chelators are more effective at reducing Fe uptake from transferrin than inducing Fe mobilisation from cells. This may be related to their ability to intercept Fe(II) after its release from transferrin within the cell. Our studies indicate that their Fe chelation efficacy is due, at least in part, to the fact that these ligands and their Fe(II) complexes are neutral at physiological pH (7.4) and sufficiently lipophilic to permeate cell membranes.

Novel diaroylhydrazine ligands as iron chelators: coordination chemistry and biological activity.

The search for orally effective drugs for the treatment of iron overload disorders is an important goal in improving the health of patients suffering diseases such as beta-thalassemia major. Herein, we report the syntheses and characterization of some new members of a series of N-aroyl-N'-picolinoyl hydrazine chelators (the H2IPH analogs). Both 1:1 and 1:2 Fe(III):L complexes were isolated and the crystal structures of Fe(HPPH)Cl2, Fe(4BBPH)Cl2, Fe(HAPH)(APH) and Fe(H3BBPH)(3BBPH) were determined (H2PPH=N,N'-bis-picolinoyl hydrazine; H2APH=N-4-aminobenzoyl-N'-picolinoyl hydrazine, H23BBPH=N-3-bromobenzoyl-N'-picolinoylhydrazine and H24BBPH=N-(4-bromobenzoyl)-N'-(picolinoyl)hydrazine). In each case, a tridentate N,N,O coordination mode of each chelator with Fe was observed. The Fe(III) complexes of these ligands have been synthesized and their structural, spectroscopic and electrochemical characterization are reported. Five of these new chelators, namely H2BPH (N-(benzoyl)-N'-(picolinoyl)hydrazine), H2TPH (N-(2-thienyl)-N'-(picolinoyl)-hydrazine), H2PPH, H23BBPH and H24BBPH, showed high efficacy at mobilizing 59Fe from cells and inhibiting 59Fe uptake from the serum Fe transport protein, transferrin (Tf). Indeed, their activity was much greater than that found for the chelator in current clinical use, desferrioxamine (DFO), and similar to that observed for the orally active chelator, pyridoxal isonicotinoyl hydrazone (H2PIH). The ability of the chelators to inhibit 59Fe uptake could not be accounted for by direct chelation of 59Fe from 59Fe-Tf. The most effective chelators also showed low antiproliferative activity which was similar to or less than that observed with DFO, which is important in terms of their potential use as agents to treat Fe-overload disease.

Iron catalysed assembly of an asymmetric mixed-ligand triple helicate.

The 2-pyridinecarbaldehyde isonicotinoyl hydrazone (HPCIH) family of ligands are typically tridentate N,N,O chelators that exhibit very high in vitro activity in mobilizing intracellular Fe and are promising candidates for the treatment of Fe overload diseases. Complexation of ferrous perchlorate with HPCIH in MeCN solution gives the expected six-coordinate complex Fe(II)(PCIH)(2). However, complexation of Fe(II) with 2-pyridinecarbaldehyde picolinoyl hydrazone (HPCPH, an isomer of HPCIH) under the same conditions leads to spontaneous assembly of an unprecedented asymmetric, mixed-ligand dinuclear triple helical complex Fe(II)(2)(PCPH)(2)(PPH), where PPH(2-) is the dianion of bis(picolinoyl)hydrazine. The X-ray crystal structure of this complex shows that each ligand binds simultaneously to both metal centres in a bidentate fashion. The dinuclear complex exhibits two well separated and totally reversible Fe(III/II) redox couples as shown by cyclic voltammetry in MeCN solution.

Cytotoxic iron chelators: characterization of the structure, solution chemistry and redox activity of ligands and iron complexes of the di-2-pyridyl ketone isonicotinoyl hydrazone (HPKIH) analogues.

Di-2-pyridyl ketone isonicotinoyl hydrazone (HPKIH) and a range of its analogues comprise a series of monobasic acids that are capable of binding iron (Fe) as tridentate ( N, N, O) ligands. Recently, we have shown that these chelators are highly cytotoxic, but show selective activity against cancer cells. Particularly interesting was the fact that cytotoxicity of theHPKIH analogues is maintained even after complexation with Fe. To understand the potent anti-tumor activity of these compounds, we have fully characterized their chemical properties. This included examination of the solution chemistry and X-ray crystal structures of both the ligands and Fe complexes from this class and the ability of these complexes to mediate redox reactions. Potentiometric titrations demonstrated that all chelators are present predominantly in their charge-neutral form at physiological pH (7.4), allowing access across biological membranes. Keto-enol tautomerism of the ligands was identified, with the tautomers exhibiting distinctly different protonation constants. Interestingly, the chelators form low-spin (diamagnetic) divalent Fe complexes in solution. The chelators form distorted octahedral complexes with Fe(II), with two tridentate ligands arranged in a meridional fashion. Electrochemistry of the Fe complexes in both aqueous and non-aqueous solutions revealed that the complexes are oxidized to their ferric form at relatively high potentials, but this oxidation is coupled to a rapid reaction with water to form a hydrated (carbinolamine) derivative, leading to irreversible electrochemistry. The Fe complexes of theHPKIH analogues caused marked DNA degradation in the presence of hydrogen peroxide. This observation confirms that Fe complexes from theHPKIH series mediate Fenton chemistry and do not repel DNA. Collectively, studies on the solution chemistry and structure of theseHPKIH analogues indicate that they can bind cellular Fe and enhance its redox activity, resulting in oxidative damage to vital biomolecules.