The study of ethanol extract of Epilobium angustifolium L. on blood sugar level in type II diabetic rats.

Epilobium angustifolium (EA) is well known as a traditional medicinal plant in many countries with multiple health effects. However, the chemical composition and anti-diabetic effect of EA has not been reported. In our study, the composition and anti-diabetic effects of ethanol extracts from EA in vivo and in streptozotocin (STZ)-induced type II diabetic rats were investigated. EA ethanol extracts exhibited protection effect on H2O2 induced oxidative stress damage INS-1 cells, reduce the body weight loss, blood glucose level and increase insulin level when compared with those of diabetic rats. Following 21 days of EA treatment at 9.2 and 18.4mg/kg, BW increased by 15.85% and 15.53%, respectively, which were extremely higher than diabetic group (9.50%). The fasting blood glucose level of EA 9.2mg/kg group rats significantly decreased by 60.43% and insulin level increased by 2.78 times, respectively. Corresponding to that, the fasting blood glucose level of EA 18.4mg/kg group rats decreased by 52.61% and insulin level increased by 2 times, respectively. Collectively our data suggest that ethanol extract of EA has remarkably hypoglycemic effect in type 2 diabetes and EA might be a promising functional food or medicine for T2DM treatment.

Physicochemical properties, immunostimulatory and antioxidant activities of a novel polysaccharide isolated from Mirabilis himalaica (Edgew) Heim.

Herbal medicines often contain bioactive polysaccharides. However, many medicinal herbs have not been explored for any active saccharides that may play key roles in their bioactivities. Herein, we extracted a novel polysaccharide from Mirabilis himalaica (Edgew) heim (denoted MHHP), a popular medicinal ingredient in traditional medicines. The structural and morphological characteristics of MHHP were measured and elucidated by high-performance gel permeation chromatography, gas chromatography connected with mass spectrometry, Fourier transform infrared and nuclear magnetic resonance spectroscopy as well as scanning electron microscopy. MHHP was homogeneous with a molecular weight of 16.1 kDa, M w/M n = 1.33, containing mainly α-d-glucan residues with (1→4)-linkage. The biological activities of MHHP upon proliferation of splenic lymphocyte, activation of related cytokine and production of nitric oxide (NO) in RAW264.7 cells were investigated in vitro. MHHP induced proliferation of mouse spleen lymphocytes and significantly promoted the secretion in TNF-α, IL-6 and NO production in RAW264.7 cells. Meanwhile, MHHP exhibited relatively low antioxidant abilities. Our data suggested that MHHP may have potential immunoregulatory and anti-inflammatory activity, with a moderate antioxidant activity.

Synergistic Regulation of Microglia Gene Expression by Natural Molecules in Herbal Medicine.

The activated microglia contribute to stroke-induced neuroinflammation by upregulating the expression of a pleura of genes that are characterized as either proinflammatory or anti-inflammatory. The natural products alantolactone (Ala) and dehydrodiisoeugenol (Deh) found in Inula helenium L. and Myristica fragrans Houtt., respectively, are regularly used in traditional herb medicine, which play anti-inflammatory and antioxidant roles via regulation of canonical pathways such as nuclear factor kappa B (NF-κB) in microglia and microphages. To illustrate the full spectra of gene expression alteration in microglia treated with Ala, Deh, and the mixture of Ala and Deh (denoted as Mix), we performed RNA-seq analysis of total RNA extracted from lipopolysaccharide- (LPS-) treated microglia subsequently exposed to Ala, Deh, and Mix. While both chemicals regulated the gene expression that facilitates an anti-inflammatory polarization, the mixture exerted some distinctive synergic regulatory effect, which differed from either of the chemicals alone. Our data provide important evidence for further research on the therapeutic mechanism of traditional medicine including Eerdun Wurile (EW).

Bioactive components of ethnomedicine Eerdun Wurile regulate the transcription of pro-inflammatory cytokines in microglia.

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional Mongolian medicine Eerdun Wurile (EW) has remarkable neural recovery effect, and has been playing a key role in the clinical treatment of neurological disorders including ischemic stroke in Inner Mongolia Autonomous Region of China. The preliminary pharmacological studies in animal suggested that EW regulates the expression of trophic factors in brain lesion and may also balance the polarization of activated microglia (Gaowa et al., 2018). AIM OF THE STUDY: The pool of leading bioactive chemicals underlying the therapeutic effects of EW has not been identified. Therefore, the mechanism of action of EW is poorly understood. This study was aimed to identify the major group of compounds that contribute to the inhibition of neuroinflammation during stroke recovery through regulation of microglia polarization. MATERIALS AND METHODS: The extracts of EW in different solvents were evaluated for their inhibitory ability of cytokine (IP-10) expression in LPS stimulated BV2 cells. The most effective extract (of petroleum ether extract) was further separated to 18 fractionations on a semi-preparative HPLC column, which were assess for the IP-10 down-regulation efficiency by RT-qPCR. The potent isolate was further fractionated in 12 fractions, which showed fewer peaks. The fraction 6 from this isolates, which remarkably down-regulates cytokines expression including IP-10, TNFα and IL-1ß, was analyzed on UPLC-qTOF MS. The key chemicals were measured for their cytokine inhibition in BV2 cells and mouse primary microglia. RESULTS: After two consecutive fractionating by preparative HPLC, petroleum ether extraction of EW gave 12 fractions with relatively distinctive chromatograms. A particular fraction (fraction 6) preserved the inhibitory effects on expression of pro-inflammatory cytokines including IP-10, TNFα, IL-1ß and iNOS. The result of UPLC-qTOF MS analysis showed that the fraction contains 21 chemicals including costunolide, alantolactone, myristicin and linolenic acid, which significantly down-regulate the expression of key pro-inflammatory cytokines in LPS stimulated BV2 cells as well as mouse primary microglia. CONCLUSION: Collectively our data suggest that the bioactive chemical pool which is responsible for the therapeutic effects of EW can be extracted in petroleum ether, and fractionated to a relatively small multiple components. Such components include known anti-inflammatory chemicals, which may contribute to the possible microglia polarization in brain lesion during the recovery of ischemic stroke.

Traditional Mongolian medicine Eerdun Wurile improves stroke recovery through regulation of gene expression in rat brain.

ETHNOPHARMACOLOGICAL RELEVANCE: Eerdun Wurile (EW) is one of the key Mongolian medicines for treatment of neurological and cardiological disorders. EW is ranked most regularly used Mongolian medicine in clinic. Components of EW which mainly originate from natural products are well defined and are unique to Mongolian medicine. AIM OF THE STUDY: Although the recipe of EW contains known neuroactive chemicals originated from plants, its mechanism of action has never been elucidated at molecular level. The objective of the present study is to explore the mechanism of neuroregenerative activity of EW by focusing on the regulation of gene expression in the brain of rat model of stroke. MATERIALS AND METHODS: Rat middle cerebral artery occlusion (MCAO) models were treated with EW for 15 days. Then, total RNAs from the cerebral cortex of rat MCAO models treated with either EW or control (saline) were extracted and analyzed by transcriptome sequencing. Differentially expressed genes were analyzed for their functions during the recovery of ischemic stroke. The expression level of significantly differentially expressed genes such as growth factors, microglia markers and secretive enzymes in the lesion was further validated by RT-qPCR and immunohistochemistry. RESULTS: Previously identified neuroactive compounds, such as geniposide (Yu et al., 2009), myristicin (Shin et al., 1988), costunolide (Okugawa et al., 1996), toosendanin (Shi and Chen, 1999) were detected in EW formulation. Bederson scale indicated that the treatment of rat MCAO models with EW showed significantly lowered neurological deficits (p < 0.01). The regional cerebral blood circulation was also remarkably higher in rat MCAO models treated with EW compared to the control group. A total of 186 genes were upregulated in the lesion of rat MCAO models treated with EW compared to control group. Among them, growth factors such as Igf1 (p < 0.05), Igf2 (p < 0.01), Grn (p < 0.01) were significantly upregulated in brain after treatment of rat MCAO models with EW. Meanwhile, greatly enhanced expression of microglia markers, as well as complementary components and secretive proteases were also detected. CONCLUSION: Our data collectively indicated that EW enhances expression of growth factors including Igf1 and Igf2 in neurons and microglia, and may stimulate microglia polarization in the brain. The consequences of such activity include stimulation of neuron growth, hydrolysis and clearance of cell debris at the lesion, as well as the angiogenesis.