Twenty million Americans suffer from peripheral nerve injury. These patients often develop chronic pain and sensory dysfunctions. In the past decade, neuroimaging studies showed that these changes are associated with altered cortical excitation-inhibition balance and maladaptive plasticity. We tested if neuromodulation of the deprived sensory cortex could restore the cortical balance, and whether it would be effective in alleviating sensory complications. We tested if non-invasive repetitive transcranial magnetic stimulation (rTMS) which induces neuronal excitability, and cell-specific magnetic activation via the Electromagnetic-perceptive gene (EPG) which is a novel gene that was identified and cloned from glass catfish and demonstrated to evoke neural responses when magnetically stimulated, can restore cortical excitability. A rat model of forepaw denervation was used. rTMS was delivered every other day for 30 days, starting at the acute or at the chronic post-injury phase. A minimally-invasive neuromodulation via EPG was performed every day for 30 days starting at the chronic phase. A battery of behavioral tests was performed in the days and weeks following limb denervation in EPG-treated rats, and behavioral tests, fMRI and immunochemistry were performed in rTMS-treated rats. The results demonstrate that neuromodulation significantly improved long-term mobility, decreased anxiety and enhanced neuroplasticity. The results identify that both acute and delayed rTMS intervention facilitated rehabilitation. Moreover, the results implicate EPG as an effective cell-specific neuromodulation approach. Together, these results reinforce the growing amount of evidence from human and animal studies that are establishing neuromodulation as an effective strategy to promote plasticity and rehabilitation.
20 March 2018 in ACS Applied Materials & Interfaces
A high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method was established for the determination of seven monosaccharides in Polygonatum sibiricum and Polygonatum odoratum. The polysaccharides were de-esterified, extracted, hydrolyzed and derivatized with p-aminobenzoic acid (PABA) to obtain fluorescently labeled monosaccharide compounds, which were finally detected by HPLC-FLD. Inertsil ODS-3, C18 chromatographic column (250 mm × 4.6 mm, 5 μm) was used for chromatography. The excitation wavelength (Ex) was 313 nm, and the emission wavelength (Em) was 358 nm. Ethyl acetate extraction reduced the peaks of chromatogram and improved the detection sensitivity than other agents. The established method had high sensitivity, strong specificity, good linear relationship and recovery efficiency. The results showed that the roots and fibrous roots of Polygonatum sibiricum and Polygonatum odoratum contained these seven monosaccharides, and the highest monosaccharide content was mannose. The method of PABA-HPLC-FLD for determination of monosaccharide content in Polygonatum sibiricum and Polygonatum odoratum was sensitive and accurate. The method established in this work provides a feasible analytical tool for the study of polysaccharides, and the findings on polysaccharides from Polygonatum sibiricum and Polygonatum odoratum can provide guidance for the natural medicine industry.
Fritillaria is a perennial herb with bulbs with multiple medicinal usages. Here, we optimized extraction and hydrolysis methods for different species and origins of Fritillaria to study their anti-inflammatory activities. Using ultrasound-assisted hot water extraction after hydrolysis by hydrochloric acid and trifluoroacetate (TFA), monosaccharide derived from 1-phenyl-3-methyl-5-pyrazolone (PMP) was separated by using HPLC. The optimal conditions for hot water extraction were found via single factor analysis and orthogonal experiments. The PMP derivatization HPLC method could accurately determine the Mannose (Man), Glucose (Glu), Galactose (Gal), Xylose (Xyl), and Fucose (Fuc) content values in Fritillaria. This pre-column derivatization method is simple and rapid, providing less variation, high sensitivity and good reproducibility for saccharide separation. To study Fritillaria's anti-inflammatory effects in a mouse swelling model, HE-staining was performed to observe morphological changes in liver and kidney samples. Fritillaria's active ingredients could significantly inhibit mouse ear swelling induced by xylene and inhibit toe swelling induced by egg white. They mainly inhibited the secretion of inflammatory cytokines inside the body and maintained the dynamic balance between pro-inflammatory and anti-inflammatory factors in the body. According to histopathological analysis, Fritillaria had good anti-inflammatory activity against LPS-induced inflammation, reducing the expression of inflammatory cytokines.