Neuroprotective Effects of Dammarane Sapogenins Against lipopolysaccharide-induced Cognitive Impairment, Neuroinflammation and Synaptic Dysfunction.

Neuroinflammation is a critical driver in the pathogenesis and progression of neurodegenerative disorders. Dammarane sapogenins (DS), a deglycosylated product of ginsenoside, possess a variety of potent biological activities. The present study aimed to explore the neuroprotective effects of DS in a rat model of neuroinflammation induced by intracerebroventricular injection of lipopolysaccharide (LPS). Our study revealed that DS pretreatment effectively improved LPS-induced associative learning and memory impairments in the active avoidance response test and spatial learning and memory in Morris water maze test. DS also remarkably inhibited LPS-induced neuroinflammation by suppressing microglia overactivation, pro-inflammatory cytok ine release (TNF-α and IL-1ß) and reducing neuronal loss in the CA1 and DG regions of the hippocampus. Importantly, pretreatment with DS reversed LPS-induced upregulation of HMGB1 and TLR4 and inhibited their downstream NF-κB signaling activation, as evidenced by increased IκBα and decreased p-NF-κB p65 levels. Furthermore, DS ameliorated LPS-induced synaptic dysfunction by decreasing MMP-9 and increasing NMDAR1 expression in the hippocampus. Taken together, this study suggests that DS could be a promising treatment for preventing cognitive impairments caused by neuroinflammation.

Diosgenin, a steroidal sapogenin, arrests arthritis through modulation of inflammatory cytokines and oxidative stress biomarkers in Wistar rats.

Diosgenin (DGN) is a well-known steroidal sapogenin that is obtained from the hydrolysis of dioscin. The current research aimed to explore the anti-inflammatory and anti-arthritic potential of DGN alone and in combination with methotrexate (MTX). The in-vitro antioxidant, and anti-arthritic potential was assessed by protein denaturation and Human red blood cell membrane stabilization assays. The in-vivo anti-inflammatory effect was examined by carrageenan-induced paw edema and xylene-induced ear edema methods. The arthritis was induced in Wistar rats by inoculation of 0.1 ml Complete Freund's adjuvant in the left hind paw at day 1. The arthritic animals received MTX 1 mg/kg as standard, DGN at 5, 10, 20 mg/kg, and a combination treatment (DGN 20 mg/kg + MTX) was administered orally from 8 to 28th day while normal and disease control received normal saline. DGN at 1600 µg/ml exhibited the highest in-vitro activities in contrast to other tested concentrations. DGN at 20 mg/kg exhibited the maximum (p < 0.05-0.0001) inhibition of inflammation in carrageenan and xyleneinduced edema models. Treatment with DGN and MTX alone and in combination significantly reduced the paw diameter, body weight, arthritic index, and pain. It restored altered blood parameters and oxidative stress biomarkers in contrast to the diseased control rats. DGN profoundly (P < 0.0001) downregulated mRNA expression of TNF-α, IL-1ß, NF-ĸß, and COX-2 while upregulated IL-4 and -10 in treated rats. The combination of DGN with MTX showed the highest therapeutic efficacy than individual therapy, so it can be used as an adjunct for rheumatoid arthritis treatment.

Pharmacokinetic comparison of ginsenoside metabolite IH-901 from fermented and non-fermented ginseng in healthy Korean volunteers.

ETHNOPHARMACOLOGICAL RELEVANCE: IH-901 (20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol) is a novel ginseng saponin metabolite formed by human intestinal bacteria and is known to have antitumor and antimetastatic effects. However, there has been no pharmacokinetic study of IH-901 in human beings. AIM OF THE STUDY: The aim of this study was to investigate the pharmacokinetic differences of IH-901 from fermented and non-fermented ginseng. MATERIALS AND METHODS: To investigate whether the pharmacokinetics of IH-901 differ between fermented and non-fermented ginseng, an open label, randomized, single dose, fasting, two-period, cross-over, pharmacokinetic study was conducted. A total of 24 healthy Korean male volunteers participated in this study. All subjects were allocated into two equal groups and administered 3g of fermented or non-fermented Panax ginseng. Serial blood samples for pharmacokinetic analysis were collected in the 24 h after dosing. Plasma IH-901 concentration was measured by a validated high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Pharmacokinetic parameters including AUC(t), C(max), and T(max) were calculated by noncompartmental models in the BA-CALC program (KFDA, 2008, 1.0.0, Korea). RESULTS: After oral administration of fermented ginseng, 5 subjects experienced diarrhea. The means of AUC(t) and C(max) were significantly different between the two groups. In the fermented ginseng group, AUC(t) was 2083.09±91.97 ng h/mL, a 15.5-fold increase over that of IH-901 from the non-fermented group (134.50±63.10 ng h/mL), and the mean C(max) was 325.00±91.97 ng/mL in the fermented ginseng group, a 27-fold higher value than that in the non-fermented group (13.88±7.24 ng/mL). T(max) was 3.29±1.00 and 12.04±4.96 h in the fermented and non-fermented group, respectively. CONCLUSIONS: The results of this study showed that the pharmacokinetic parameters of IH-901 from fermented Panax ginseng are different from those of non-fermented ginseng, from which IH-901 is formed by intestinal fermentation.

Spinal estrogen receptor alpha mediates estradiol-induced pronociception in a visceral pain model in the rat.

We previously reported that 17ß-estradiol (E2) is pronociceptive in a visceral pain model in the rat. Subcutaneously (s.c.) administered E2 reversed the decrease in the colorectal distention (CRD)-evoked visceromotor response produced by ovariectomy (OVx) and CRD-induced nociceptive responses were greater in proestrous rats compared with met/diestrous rats. The site of action, the type of estrogen receptors activated, and the possible intracellular signaling pathway involved are yet to be established. In the present study, intrathecal (i.t.) E2 administered to OVx rats mimicked the effects of s.c. E2, suggesting that spinal estrogen receptors are involved. This is further supported by the observations that the anti-estrogen ICI 182,780 injected i.t. in intact female rats significantly decreased the visceromotor response to CRD, the response of colonic afferents was not affected by OVx, and colonic afferents did not label for estrogen receptor α (ERα). The ERα selective agonist, 4,4',4''-[4-propyl-(1H)-pyrazole-1,3,5-triyl]tris-phenol (PPT; s.c. or i.t.) facilitated the visceromotor response similar to E2, suggesting ERα activation is involved in mediating the pronociceptive effect of E2. PPT (s.c. or i.t.) increased the response of spinal dorsal horn neurons to CRD, indicating a spinal site of action. In addition, s.c. E2 or PPT increased CRD-induced spinal extracellular signal-regulated kinase (ERK) phosphorylation that was not observed in OVx rats and a mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitor blocked facilitation of the visceromotor response by PPT. Taken together, the present study demonstrates that spinal ERα mediates the pronociceptive effect of E2 on visceral signal processing through activation of the MAPK pathway.

[Clinical value of protoparaxotril saporlirs combined with aspirin in the secondary prevention of cerebral infarction].

OBJECTIVE: To observe the clinical value of protoparaxotril saporlirs (PTS) combined with aspirin in the secondary prevention of cerebral infarction. METHODS: The 140 patients with cerebral infarction were collected, among them the 120 patients during recovery stage were equally assigned to three groups by randomized, single blinded and open controlled principle, and they were treated respectively by PTS (A), aspirin (B), and PTS plus aspirin (C) for 6 months. The other 20, who couldn't or were unwilling to use aspirin, were arranged in group D for control. The platelet aggregation rate, incidence of stroke recurrence, gastrointestinal adverse reaction and the NIHSS scores of patients were observed during the six-month period of treatment. RESULTS: As compared with group D, the lowering amplitude of platelet aggregation rate after treatment in the three treatment groups were significantly higher (P < 0.01). Comparison of platelet aggregation rate between group A and B showed significant difference after 3-month treatment (P < 0.05), but the difference became insignificant after 6-month treatment (P > 0.05). The incidence of stroke recurrence in the group A, B and C was 18.9%, 13.2% and 10.8% respectively, which showed no significant difference among them, but all were significantly lower than that in the group D (44.4%, P < 0.05). NIHSS scores in group A and C were significantly lower than in group B (P < 0.01); and the occurrence of gastrointestinal reaction was significantly lower in group A (P < 0.01). CONCLUSION: Long-term application of PTS has the effects for preventing stroke recurrence, lowering gastrointestinal adverse reaction and improving patients' neural function in patients with stroke. As used in combination with aspirin, it shows potential practical importance in the clinical secondary prevention of stroke.

Ginsenosides 20(S)-protopanaxadiol and Rh2 reduce cell proliferation and increase sub-G1 cells in two cultured intestinal cell lines, Int-407 and Caco-2.

Ginsenosides derived from 20(S)-protopanaxatriol (PT) and 20(S)-protopanaxadiol (PD) groups had similar characteristic cytotoxic effects on the growth of two intestinal cells lines, Int-407 and Caco-2. Pure Rh2, a ginsenoside structurally related to PD, inhibited intestinal cell growth at greater than twice the concentration of PD, while Rh1, a ginsenoside structurally related to aglycone PT, had no cytotoxic effect. Concentrations causing growth inhibition of 50% of cells (LC50) for the compounds PD, PT, and Rh2 were 23, 26, and 53 microg/mL, respectively, for Int-407 cells. In comparison, the LC50 for PD and PT was determined to be 24 microg/mL, and that for Rh2 was 55 microg/mL in Caco-2 cells. A standardized North American ginseng extract with a known ginsenosides composition did not induce cytotoxicity in either of the intestinal cell lines. Cell cycle analysis showed characteristically different (P = 0.05) effects of ginsenosides PD, Rh2, and PT in both cell lines. Rh2 treatment of Int-407 caused a significantly (P = 0.05) higher production of sub-G1 (apoptotic) cells (35% +/- 1%) compared with untreated cells (14% +/- 0.3%) after 24 h. PD and Rh2 treatments were both significantly (P < 0.05) higher in apoptotic cells than in untreated cells after 48 and 72 h. Similar results were obtained for treatment of Caco-2 cells. Lactate dehydrogenase (LDH) activity in both cell lines was similar for PD and Rh2 and higher (P = 0.05) than for PT treatment at most time periods. These results show a specific structure-function relationship for bioactive ginsenosides in two contrasting intestinal cell types.