Investigation into anti-epileptic effect and mechanisms of Ganoderma lucidum polysaccharides in in vivo and in vitro models

Abstract

There are about 60 million epileptic patients worldwide. Finding a more effective antiepileptic drug with fewer side effects is of continuing importance (1) . Ganoderma lucidum, a mushroom having been used as Traditional Chinese Medicine, has showed the effect of antiepileptic effect with no side-effects (2) . The aim of the present study was to assess the mechanisms of antiepileptic effects by Ganoderma lucidum polysaccharides (GLP).In study 1, effect of GLP on calcium turnover, Ca 2+ /calmodulin-dependent protein kinase type II α (CaMKII α) and ERK1/2 expression was investigated using primary hippocampal neurons from <1 day old rats. Neurons were cultured with normal medium (Control group), or Mg 2+ free medium (Model I group) for 3 hours; neurons were incubated with Mg 2+ free medium without GLP (Model II group), or with GLP (0·375 mg/ml) (GLP I group) for 3 hours and then cultured with the normal medium for an extra 3 hours; neurons were incubated with Mg 2+ free medium for 3 hours and then cultured with a normal culture medium containing GLP for an extra 3 hours (GLP group II). In study 2, male Wistar rats (n = 60) were randomly divided into A) Control group; B) PBS group; and C) Epilepsy group: rats were given kainic acid (1·5 μg/μl was injected into hippocampus), then they were given GLP (i.p.) once a day for 7 days, GLP doses were D), 25 mg/kg; E), 50 mg/kg), and F, 100 mg/kg, respectively. Rat behavior and EEG were recorded. The number of immunohistochemical staining caveolin-1(Cav-1) and NF-κB positive cells was counted.In study 1, GLP treatment increased CaMKIIα expression, and decreased calcium turnover. ERK1/2 had higher expression in cytoplasm and nucleus in Model groups compared with the normal Control groups (P < 0·01). In GLP group, the expression of ERK1/2 (Fig. 1) was inhibited. In study 2. Epileptic symptoms in rats of group C, D, E and F were observed in 7 minutes after kainic acid injection. In day 7, normal EEG, with lower wavelength of α and β wave, was recorded in group A and B; sharp and frequent wavelength was observed in group C, D, E or F (Fig. 2). Even more, compared to group C, more waves with lower wavelength existed in group D, E or F. The frequency of epilepsy discharge from initial 10-15/min reduced to 1/min after GLP treatment. Cav-1 positive cells (Fig. 2) and NF-κB positive cells in group C were significantly higher compared with group A and B. Compared with group C, GLP treatments further increased Cav-1 positive cells, but decreased NF-κB positive cells.In conclusion, GLP improved the epileptic behavior; inhibited calcium overloading and ERK1/2 and NF-KB expression; also stimulated CaMK II α and Cav-1 expression.

Effects and Mechanism of Ganoderma lucidum Polysaccharides in the Treatment of Diabetic Nephropathy in Streptozotocin-Induced Diabetic Rats

“…Several extracts of Ganoderma lucidum showed amelioration in this progress in a review [50], e.g., one study [51] showed that proteoglycan isolated from Ganoderma lucidum fruiting bodies shows protection renal morphology in diabetic mice in a dosedependently (75, 250, and 450 mg/kg) manner during a 8week treatment. According to previous research, the mechanism appears also via directly elimination reactive oxygen species, suppresses lipid peroxidation, and indirectly scavenges the radicals via activating antioxidant enzyme systems and chelation with metal ion by forming crossbridge between carboxyl groups decreasing reactive oxygen species generation [52][53][54][55][56][57][58][59][60]. This study showed that the expressions of the inflammatory factors IL-6, IL-1β, and TNF-α in the diabetic group were significantly increased, while they were reduced significantly after GLP treatment.…”

Investigation into Antiepileptic Effect of Ganoderic Acid A and Its Mechanism in Seizure Rats Induced by Pentylenetetrazole

“…Hematoxylin-Eosin (H&E) Staining. The rat brain tissues fixed with 4% paraformaldehyde were cut into 4 μm sections and stained with H&E as described previously [42], and the histological structure was observed using a 400x microscope (Nikon ECLIPSE Ni, Japan). Damaged neurons from 6 observed optical fields per rat were counted and used for the statistical analysis among groups.…”

Food-Derived Antioxidant Polysaccharides and Their Pharmacological Potential in Neurodegenerative Diseases

“…In addition, a variety of chemical interventions, including excitatory amino acids such as glutamate, N -methyl- d -aspartate (NMDA) and kainic acid; neurotoxins such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 6-hydroxydopamine (6-OHDA); and ageing-promoting agents such as d -galactose, are also shown to induce neurodegenerative symptoms via oxidative and inflammatory stresses [ 83 , 99 , 100 ]. As oxidative stress plays a pivotal role in neurodegeneration, antioxidant strategies, including food-derived antioxidant polysaccharides, are shown to attenuate neuronal damage and improve cognitive and motor functions in a range of neurodegenerative models ( Table 2 ) [ 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142...…”

“…For instance, L. barbarum polysaccharide can increase cell viability and suppress JNK activation in glutamate-exposed rat primary cortical neurons [ 129 ], suggesting an involvement of MAPK pathway in the neuroprotective effect of the polysaccharide. Another example is G. lucidum polysaccharide, which is shown to alleviate epileptic symptoms and up-regulate the expression of calcium/calmodulin-dependent protein kinase II, a kinase that plays an important role in calcium transfer in neurons, in kainic acid-injected rats [ 123 ]. As calcium overload mediates excitatory amino acid-induced neurotoxicity [ 164 ], prevention of calcium transporting may contribute to this neuroprotective effect of G. lucidum polysaccharide.…”