Pycnogenol achieves neuroprotective effects in rats with spinal cord injury by stabilizing the mitochondrial membrane potential

ABSTRACT

Objectives

In this study, we aimed to verify the neuroprotective effects of pycnogenol (PYC) on spinal cord injury (SCI) and to determine the underlying mechanisms.     

Hepatoprotective effect of Pandanus odoratissimus seed extracts on paracetamol-induced rats

ContextPandanus odoratissimus Linn. (Pandanaceae) seed extract is known to have antioxidant activities. However, the potential hepatoprotective effect is still unclear.ObjectiveTo investigate the hepatoprotection aspect of P. odoratissimus methanol extract towards paracetamol-induced rats.Materials and methodsThirty male Sprague–Dawley rats were randomly divided into six equal groups: one group served as the healthy control and five groups with hepatotoxicity (hepatotoxic control and 4 treatment groups). The oral treatment of paracetamol-induced hepatotoxicity of 3 g/kg using three different concentrations of P. odoratissimus (300, 600 and 900 mg/kg), and silymarin (200 mg/kg) groups were administered once a day for 14 days. Enzyme activities and protein levels in serum were determined in rats at the end of the treatments. The histopathology of rat livers was observed under an electron microscope with 10× magnification.ResultsPandanus odoratissimus significantly decreased the serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP) and γ-glutamyl transferase (GGT) activities in induced-paracetamol rat serum (p < 0.05). Moreover, P. odoratissimus significantly decreased total bilirubin and direct bilirubin levels (p < 0.05). It significantly blocked the decline of serum albumin and protein levels (p < 0.05). Histopathological changes amplified paracetamol-induced liver damage and the hepatoprotective effect of P. odoratissimus in the liver.Discussion and conclusionsPandanus odoratissimus improved the hepatoprotective effect in a concentration-dependent manner by reducing related hepatic enzyme and protein markers, suggesting as a useful agent in hepatotoxicity treatment, and it can be generalized to a broader study population in different hepatotoxic animal models.     

Panton-Valentine Leucocidin of Staphylococcus aureus Induces Oxidative Stress and Neurotransmitter Imbalance in a Retinal Explant Model

PurposeEndophthalmitis models have reported the virulent role of Panton-Valentine leucocidin (PVL) secreted by Staphylococcus aureus on the retina. PVL targets retinal ganglion cells (RGCs), expressing PVL membrane receptor C5aR. Interactions between PVL and retinal cells lead to glial activation, retinal inflammation, and apoptosis. In this study, we explored oxidative stress and retinal neurotransmitters in a rabbit retinal explant model incubated with PVL.MethodsReactive oxygen species (ROS) production in RGCs has been assessed with fluorescent probes and immunohistochemistry. Nuclear magnetic resonance (NMR) spectroscopy quantified retinal concentrations of antioxidant molecules and neurotransmitters, and concentrations of neurotransmitters released in the culture medium. Quantifying the expression of some pro-inflammatory and anti-inflammatory factors was performed using RT-qPCR.ResultsPVL induced a mitochondrial ROS production in RGCs after four hours’ incubation with the toxin. Enzymatic sources of ROS, involving nicotinamide adenine dinucleotide phosphate–oxidase and xanthine oxidase, were also activated after four hours in PVL-treated retinal explants. Retinal antioxidants defenses, that is, glutathione, ascorbate and taurine, decreased after two hours’ incubation with PVL. Glutamate retinal concentrations and glutamate release in the culture medium remained unaltered in PVL-treated retinas. GABA, glycine, and acetylcholine (Ach) retinal concentrations decreased after PVL treatment. Glycine release in the culture medium decreased, whereas Ach release increased after PVL treatment. Expression of proinflammatory and anti-inflammatory cytokines remained unchanged in PVL-treated explants.ConclusionsPVL activates oxidative pathways and alters neurotransmitter retinal concentrations and release, supporting the hypothesis that PVL could induce a neurogenic inflammation in the retina.     

EFFECT OF SULFUR DIOXIDE ON ACTIVE AND PASSIVE AVOIDANCE IN EXPERIMENTAL DIABETES MELLITUS: RELATION TO OXIDANT STRESS AND ANTIOXIDANT ENZYMES

The effect of sulfur dioxide (SO₂) on hippocampus antioxidant status, lipid peroxidation and learning and memory was investigated in diabetic rats. A total of 40 rats were divided into four equal groups: Control (C), SO₂ + C (SO₂), diabetic (DM) and SO₂ + D (DMSO₂). Experimental diabetes mellitus (DM) was induced by i.v injection of alloxan with a dose of 50 mg/kg body weight. Ten ppm SO₂ was administered to the rats in the sulfur dioxide groups in an exposure chamber. Exposure occurred 1 h/d, 7 d/wk, for 6 wk; control rats were exposed to filtered air during the same time periods. SO₂ exposure, while markedly increasing Cu-Zn Superoxide dismutase activity, significantly decreased glutathione peroxidase activity in diabetic and non-diabetic groups compared with the C group; hippocampus catalase activity was unaltered. Hippocampus thiobarbituric acid reactive substances (TBARS) were found to be elevated in all experimental groups with respect to control group. The active avoidance training results indicated that diabetic condition has been associated with learning and memory impairment. SO₂ exposure caused deficits of learning and memory. Diabetes mellitus–induced impairment of learning and memory were potentiated by SO₂ exposure. These findings suggest that exposure to SO₂ by increasing lipid peroxidation, can change antioxidant enzyme activities and can elevated intensity of deficits of learning and memory in diabetic rats.     

Antioxidant treatment and outcome of cortinarius orellanus poisoning: a case series

Abstract

Objectives: To study the frequency, severity, and long-term outcome of renal injury in Cortinarius orellanus poisoning, to evaluate the association between the ingested amount of C. orellanus and outcome, and to evaluate the effect of N-acetylcysteine and corticosteroid treatment on outcome. Methods: Case series of eight patients. Diagnosis and severity of acute kidney injury (AKI) and chronic kidney disease (CKD) were classified according to current AKI and CKD definitions. N-acetylcysteine and corticosteroids were administered to six patients, former according to the standard for paracetamol poisoning. Main findings: All patients developed AKI, six in the most severe stage and four required renal replacement therapy (RRT). After 12 months, seven patients presented with CKD, of whom three required chronic RRT and further two were in advanced CKD. AKI and CKD severity highly correlated with the consumed amounts of Cortinarius orellanus (r?=?0.98, p?<?0.001 and r?=?0.78, p?=?0.02, respectively) but not with N-acetylcysteine and corticosteroid treatment. Conclusions: AKI and CKD by current definitions and classifications are frequent and severe after Cortinarius orellanus poisoning. The ingested amount of Cortinarius orellanus correlates with the severity of both AKI and CKD. N-acetylcysteine and corticosteroid treatment do not seem to have a beneficial effect on either AKI or CKD.     

Sacchachitin,a novel chitin-polysaccharide conjugate macromolecule present in Ganoderma lucidum: Purification,composition, and properties

Context: The extraction method and the crude wound healing effects of sacchachitin from Ganoderma tsugae Murr. (Ganodermataceae) has been cited. However, its purity is still largely limited.

Objective: An improvement of the fractionation protocol to purify the sacchachitin from Ganoderma lucidum L. (Ganodermataceae) (SGL) is needed.

Methods: Fruiting bodies were extracted with double distilled water and subsequently the residue treated with 95% ethanol and then 40% ethanol. After being filtered, the pH of the supernatant was adjusted to 4.0 with 1 N HCl and lyophilized. The supernatant was added (3:1 v/v) ethanol, the precipitate was collected, 2% NaOH was added and refluxed. The supernatant was collected with pH adjusted to 4.0, then treated with 10% potassium hydroxide (KOH) with repeating acid precipitation and (3:1) ethanol precipitation twice more to obtain the sacchachitin.

Results: SGL had a hexosamine content 16.3% (w/w), firmly linked to a talomannan. Its Fourier Transform Infrared Spectroscopy (FTIR) spectrum revealed specific absorption (in cm^–1) ν_O–H 3455.5 b,s, amide ν_C=O 1678.5, and amide I° δ_N–H 1550.4. The percentage deacetylation degree was 37.6 and 39.4% for SGL and MSC, respectively. As contrast, MSC contained only 6.6% of hexosamine with a low protein/carbohydrate ratio 0.35 comparing to 0.82 for SGL. SGL was only moderately strong antioxidant regarding the anti-DPPH, antihydroxyl free radical, and antisuperoxide anion capabilities, exhibiting an IC₃₃ values of 10?mg/mL (the highest scavenging capability never exceeding 33%), 0.9?mg/mL, and 4.8?mg/mL, respectively.

Conclusion: We have successfully isolated the pure sacchachitin from the fruiting bodies of G. lucidum that exhibits potent antioxidative activity and may be useful in fabrication of the artificial skin composite substitute.     

Effects of co-fermentation by Saccharomyces cerevisiae and Issatchenkia orientalis on sea buckthorn juice

This work relates to the development of a co-fermented product of sea buckthorn (Hippophae rhamnoides L.) with Saccharomyces cerevisiae and Issatchenkia orientalis. Besides malic acid degradation, the parameters of present production technology were also standardized with emphasis on the retainability of total phenolic content (TPC) of sea buckthorn juice. The effect of co-fermentation on physico-chemical characteristics, organic acids, flavonoids, TPC and antioxidant activities was studied. The high-performance liquid chromatography (HPLC) analysis showed 55% reduction in malic acid content after the co-fermentation of sea buckthorn juice. The TPC of sea buckthorn product was 2.18 g gallic acid equivalent (GAE)/l. The estimated scavenging effect on 2,2-diphenyl-1-picrylhydrazyl free radicals was 2.63 Trolox equivalent (TE) mmol/l. Ferric-reducing antioxidant power and 2,2′-azino-bis(3-ethylbenz-thiazoline-6-sulphonic acid) assays also showed that sea buckthorn product was on a par with commercial wines (Cabernet Shiraz and Beaujolais). We conclude that the process of co-fermentation resulted in a significant antioxidant potential of sea buckthorn product.     

芡实醇提物对糖尿病肾病大鼠肾功能的影响及其体外抗氧化能力测定

目的 探讨芡实醇提物对糖尿病肾病大鼠肾功能的影响,并测定芡实醇提物、水提物上清和沉淀的体外抗氧化能力。方法 80%乙醇提取芡实种仁,浓缩冻干后得干燥粉末,药渣采用水提醇沉法,经抽滤旋蒸制备上清和沉淀。雄性SD大鼠腹腔注射链脲佐菌素60 mg/kg诱导糖尿病肾病模型,灌胃给予芡实醇提物(75、150、300、600 mg/kg)12周后,检测大鼠尿蛋白、尿微量白蛋白、血肌酐(Cr)和尿素氮(BUN)含量,并观察肾组织病理学变化。通过对Fe3+还原力、1,1-二硝基-2-三硝基苯肼(DPPH)、O2-和OH-自由基清除率的比较,测定3种提取物的抗氧化能力。结果 与糖尿病肾病模型组比较,各剂量芡实给药组均能降低大鼠24 h尿蛋白和尿微量白蛋白含量,芡实150和600 mg/kg组尿蛋白显著降低(P<0.05);与模型组比较,各剂量芡实给药组大鼠血中BUN均有不同程度降低,芡实300 mg/kg组降低更为显著(P<0.01)。12周末肾组织病理学观察结果表明,芡实醇提物300和600 mg/kg能够明显减轻肾组织损伤。芡实醇提物在浓度为0.6、0.8和1.0 mg/ml时,显示有一定的抗氧化能力,表现为对Fe3+的还原,对DPPH、O2-和OH-的清除。结论 芡实醇提物具有降低糖尿病肾病大鼠尿蛋白的作用,该作用可能与其抗氧化能力有关。     

氧化应激致心室重构的研究进展

心室重构意味着血管壁中氧化应激水平的提高,当机体受到有害刺激时,氧化和抗氧化之间失衡,导致大量活性氧簇（ ROS）的产生,加速心室重构的进展。近年来,新型抗氧化剂成为治疗或预防心室重构的靶点,观察抗氧化剂治疗在心室重构患者的长期应用是当下趋势。该文就氧化应激与心室重构之间的关系及相关药物治疗进行综述。