Objective To investigate the neuroprotective effect of conducting hydrogel loaded with tetramethylpyrazine sustained-release microparticles (hereinafter referred to as “TGTP hydrogel”) on spinal cord injury rats. Methods Forty-eight adult female Sprague Dawley rats were randomly divided into 4 groups: sham operation group (group A), model group (group B), conductive hydrogel group (group C), and TGTP hydrogel group (group D), with 12 rats in each group. Only laminectomy was performed in group A, and complete spinal cord transection was performed in groups B, C, and D. Basso-Bettie-Bresnahan (BBB) score was used to evaluate the recovery of hind limb motor function of each group before modeling and at 1, 3, 7, 14, and 28 days after modeling, respectively. At 28 days after modeling, the rats were sacrificed for luxol fast blue (LFB) staining to detect myelin regeneration. Nissl staining was used to detect the survival of neurons. Immunohistochemical staining was used to evaluate the expression of inflammation-related factors [nuclear factor кB (NF-кB), tumor necrosis factor α (TNF-α), and interleukin 10 (IL-10)]. Immunofluorescence staining and Western blot were used to evaluate the expression of neurofilament 200 (NF200). RseultsBBB scores of group A were significantly better than those of the other three groups at all time points after modeling (P<0.05); at 14 and 28 days after modeling, there was no significant difference in BBB scores between groups C and D (P>0.05), but the BBB score of group D was significantly better than that of group B (P<0.05). LFB staining and Nissl staining showed that the structure of neurons and myelin in group A was intact, and the myelin integrity and survival number of neurons in group D were significantly better than those in groups B and C. Immunohistochemical staining showed that the absorbency (A) value of NF-кB and TNF-α in group A were significantly lower than those in groups B and C (P<0.05), the A value of IL-10 was significantly higher than that in the other three groups (P<0.05); the A value of NF-κB in group D was significantly lower than that in groups B and C, the A value of TNF-α in group D was significantly lower than that in group B, while the A value of IL-10 in group D was significantly higher than that in group B (P<0.05). Immunofluorescence staining showed that the structure of neurons and nerve fibers in group A was clear and the fluorescence intensity was high. The fluorescence intensity of NF200 in group D was higher than that in groups B and C, and some nerve fibers could be seen. Western blot analysis showed that the relative expression of NF200 in group A was the highest, and the relative expression of NF200 in group D was significantly higher than that in groups B and C (P<0.05). Conclusion The TGTP hydrogel can effectively promote the recovery of motor function in rats with spinal cord injury, and its mechanism may be related to the regulation of inflammatory response.
Objective To explore the mechanisms for repairing spinal cord injury (SCI) with tetramethylpyrazine-loaded electroconductive hydrogel (hereinafter referred to as “TGTP”). Mehtods A total of 72 female Sprague-Dawley rats were randomly divided into 4 groups: sham operation group (group A), SCI group (group B), SCI+electroconductive hydrogel group (group C), and SCI+TGTP group (group D). Only the vertebral plate was removed in group A, while the remaining groups were subjected to a whole transection model of spinal cord with a 2 mm gap in the lesions. The recovery of hindlimb motor function was evaluated by Basso, Beattie, Bresnahan (BBB) score and modified Rivlin-Tator inclined plate test before operation and at 1, 3, 7, 14, and 28 days after operation, respectively. Animals were sacrificed at 7 days and 28 days after modeling. Neovascularisation was observed by immunofluorescence staining of CD31 and the expression levels of angiopoietin 1 (Ang-1) and Tie-2 were assessed by Western blot assay. At 28 days postoperatively, the expression levels of pro-angiogenic related proteins, including platelet-derived growth factor B (PDGF-B), PDGF receptor β (PDGFR-β), vascular endothelial growth factor A (VEGF-A), and VEGF receptor 2 (VEGFR-2), were also assessed by Western blot. The fibrous scar in the injured area was assessed using Masson staining, while neuronal survival was observed through Nissl staining. Furthermore, LFB staining was utilized to detect myelin distribution and regeneration. Immunofluorescence and Western blot assay were employed to evaluate the expression of neurofilament 200 (NF200). Results The hindlimb motor function of rats in each group gradually recovered from the 3rd day after operation. The BBB score and climbing angle in group D were significantly higher than those in group B from 3 to 28 days after operation, and significantly higher than those in group C at 14 days and 28 days after operation (P<0.05). Masson staining showed that the collagen volume fraction in groups B-D were significantly higher than that in group A, and that in group D was significantly lower than that in groups B and C (P<0.05); a small amount of black conductive particles were scattered at the broken end in group D, and the surrounding collagen fibers were less than those in group C. Nissl and LFB staining showed that the structure of neurons and myelin sheath in the injured area of spinal cord in group D was relatively complete and continuous, and the number of Nissl bodies and the positive area of myelin sheath in group D were significantly better than those in groups B and C (P<0.05). NF200 immunofluorescence staining and Western blot assay results showed that the relative expression of NF200 protein in group D was significantly higher than that in groups B and C (P<0.05). CD31 immunofluorescence staining showed that the fluorescence intensity of group D was better than that of groups B and C at 28 days after operation, and tubular or linear neovascularization could be seen. The relative expressions of Ang-1 and Tie-2 proteins in group D were significantly higher than those in groups B and C at 7 and 28 days after operation (P<0.05). The relative expressions of PDGF-B and PDGFR-β proteins in group D were significantly higher than those in groups B and C, and group B was significantly higher than group C at 28 days after operation (P<0.05). The relative expressions of VEGF-A and VEGFR2 proteins in group D were higher than those in groups B and C, showing significant difference when compared with group B (P<0.05), but only the expression of VEGF-A protein was significantly higher than that in group C (P<0.05). There was significant difference only in VEGFR-2 protein between groups B and C (P<0.05). Conclusion TGTP may enhance the revascularization of the injured area and protect the neurons, thus alleviating the injury of spinal cord tissue structure and promoting the recovery of neurological function after SCI in rats.
Objective To investigate the effect of tetramethylpyrazine (TMP) with a certain concentration added to vitrification solution on peripheral nerve allografts regeneration. Methods Forty-eight healthy clean SD male rats were selected as donors, and 96 healthy clean Wistar male rats as recipients, all rats being 3 months old and weighing 200-250 g. The sciatic nerves segments of 15 mm were removed from the donors, then randomly divided into 4 groups according to vitrificationsolution containing TMP. No TMP was used in group A as the control group; 100 mg/L, 200 mg/L and 400 mg/L TMP were used in group B, group C and group D, respectively. Then them were cryo-preserved at — 196 ℃ for 3 weeks. Nerve defect of 10 mm in length was made in the sciatic nerves of recipients. After rewarming, the allografts were transplanted to the corresponding rats. The gross appearance, the morphological and electrophysiological changes, the image analysis of axons and motor end-plate were detected at 4, 8, 12 and 16 weeks. Results All rates survived to the end of the experiment. The adhesion and edema of allografts in group A and group B were obvious 4 weeks after operation; then adhesion and edema was obvious in group A and were improved in the other groups 8 weeks after operation. Adhesion was observed in groups A and B; no adhesion was observed in groups C and D at 12 weeks. The number of regeneration nerve, the latent, the ampl itude, the nerve conduction velocity, the medullary sheath/μm2, the medullary sheath density/μm2 and the image analysis of axons and motor end-plate in groups A and B were significantly lower than those in groups C and D (P lt; 0.01); and there were no significant differences between groups C and D (P gt; 0.05). The observation of transmission electron microscope showed that medullated nerve fibers and myel in sheath of groups C and D were thicker than groups A and B, layers of groups C and D were clear. Conclusion The vitrification solution with 200 mg/L tetramethylpyrazine has protective effect on regeneration of peripheral nerve allografts．
Objective To investigate the effect of Ligustrazine on the expressions of FoXO3a, MAFbx, and MuRF1 indenervated skeletal muscle atrophy rats. Methods Fifty-four 8-week-old female Sprague Dawley rats were randomly dividedinto 3 groups: normal control group (group A, n=6), denervated control group (group B, n=24), and Ligustrazine interventiongroup (group C, n=24). After the denervated gastrocnemius models were established in the rats of groups B and C, sal ine andLigustrazine [80 mg/(kg·d)] were given every day by intraperitoneal injection, respectively. However, no treatment was donein group A. At 2, 7, 14, and 28 days after denervation, the wet weight of gastrocnemius was measured to calculate the ratio ofwet weight. The mRNA and protein expression levels of FoXO3a, MAFbx, and MuRF1 were detected by RT-PCR and Westernblot. Results The ratio of gastrocnemius wet weight decreased with time after denervation in groups B and C, showingsignificant differences when compared with that of group A (P lt; 0.05), and group C were significantly higher than that of groupB at 7, 14, and 28 days (P lt; 0.05). The mRNA and protein expressions of FoXO3a, MAFbx, and MuRF1 in groups B and Cwere significantly higher than those in group C at 7, 14, and 28 days (P lt; 0.05), and group C was significantly lower than groupB (P lt; 0.05). Conclusion Ligustrazine may postpone denervated skeletal muscle atrophy by reducing mRNA and proteinexpressions of FoXO3a, MAFbx, and MuRF1.
In order to investigate the inhibitory effect of salvia miltiorrhiza (SM) and tetramethyl pyrazine (TP) on scartricial fibroblast, the hypertrophic scar tissue of chest was chosen for culture of fibroblasts, and the influence of SM and TP on fibroblasts was observed, The effect of the drugs on the growth of fibroblasts, on DNA synthesis of fibroblasts and on mitosis index of fibroblasts were all determined quantitatively. The results showed: 1. SM and TP could inhibit significantly the growth of the fibroblasts, the inhibitory effect was irreversible when the concentration of the drugs reached 5 mg/ml and 500 micrograms/ml respectively; 2. SM and TP could inhibit the absorption of 3H-TdR and this effect was correlated positively to the dosage of the drugs and; 3. SM and TP could reduce the mitosis index of fibroblasts. It was concluded that SM and TP had definite depressive effect on growth of fibroblasts which was correlated positively with the concentration of drugs and duration of application. The inhibitory effect of the drugs on fibroblasts was mainly through inhibition of synthesis of DNA.
Objective:To observe the intervention effect of the tetra methylpyraz ine on the rds mice with retinitis pigmentosa.
Methods:A total of 84 rds mice were randomly divided into 2 groups, with 42 mice in each group. The mice in the experimental group underwent intraperitoneal cavity injection with hydrochlor i c tetramethylpyrazine (80 mg/kg, twice per day) at the date of birth and till 35 days after birth, whereas the normal saline was injected into the intraperito n eal cavity of rats in the control group. The mice were sacrificed 0, 3, 7, 14, 2 1, 28, 35 days after birth, and the eyeballs were enucleated for the routine pat hologic examination with the light microscope. The apoptosis of photoreceptor ce ll nuclei was detected by terminal deoxynucleotidyl transferasemediated dUTP n i ck endlabeling (TUNEL) technigue and the expression of bcl2 in retina was de tect by immunohistochemistry method.
Results:The results of li ght microscopy s howed that the layer number of retinal photoreceptor cell nuclei with tetramethy lpyrazine treatment was increased 14, 21, 28, 35 days after the treatment compar ed with that in the control group（P＜0.01）. The results of electron-micro scope suggested that tetramethylpyrazine might reduce lesions in the photoreceptor cells and the destruction of the disc member, mitochondrion，and outer limiting me mbrane in the photoreceptor outer segment in rds mice. The apoptosis of the phot oreceptor cell nuclei reduced in rds mice 3, 7, 14, 21, 28 and 35 days after the treatment compared with that in the control group （P＜0.01）. The express ion of bcl-2 in the matrix of retinal photoreceptor cell nuclei and its inner and o u ter segments increased significantly in rds mice 3，7, 14, 21, 28 and 35 days af ter the treatment （P＜0.05）.
Conclusions:Tetramethylpyra zine might reduce ret inal photoreceptor apoptosis by upregulating the expression of bcl-2 in the m at rix of retinal photoreceptor cell nuclei or its inner and outer segments in rds mice.
Objective To evaluate the efficacy and safety of tetramethylpyrazine (TMP) for diabetic peripheral neuropathy (DPN). Methods Randomized controlled trials were identified from CBM (1978-2003.3), TCMLRS (1980-2003.3), Medline (1970-2003.3), EMbase (1970-2003.3) and Cochrane Library (issue 3, 2003). We handsearched Journal of Traditional Chinese Medicine (1990-2002), New Chinese Medicine (1990-2002), Chinese Journal of Integrated Traditional and Western Medicine (1990-2002) and Research of Traditional Chinese Medicine (1990-2002). Papers of the controlled trials of clinical therapeutic studies on DPN treatment by Chinese medicine herb TMP were included and analyzed according to the criteria of the Cochrane Handbook in 1997. Results Six RCTs involving 669 patients were included, with all trials of low methodological quality. Meta-analysis indicated TMP was more effective than western medicine on pain or numbness of extremities of DPN [The pooled OR = 10.12, 95%CI (6.70 to15.28), P=0.000] and motor nerve conduction velocity change of common peroneal nerves and median nerves . Only one trial reported the side effects of TMP, such as dizziness and headache. Conclusions Based on the review, TMP infusion may have positive effect on DPN. However, the evidence is not b enough due to the general low methodological quality, so we can’t draw a reliable conclusion about the effects of TMP for DPN at the moment. Further large randomized, double blind, placebo-controlled trial are needed.
Objective To observe the effect of tetramethypyrazine (TMP) on the expression of hypoxia-related factors in human umbilical vein endothelial cells (HUVECs). Methods The second to fifth passage cultured HUVECs were divided into five groups: control group, CoCl2induced hypoxic group and 50, 100, 200 mu;mol/L TMP treatment groups. HUVECs in control group were not treated. HUVECs inCoCl2induced hypoxic group were treated with 150 mu;mol/LCoCl2for four hours. HUVECs in 50, 100, 200 mu;mol/L TMP treated groups were pretreated with 150 mu;mol/LCoCl2 for four hours, followed by treatment with 50, 100, 200 mu;mol/L TMP for eight hours. Real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA levels of prolyl hydroxylase 2 (PHD2), hypoxia-induced factor-1alpha;(HIF-1alpha;) and vascular endothelial growth factor (VEGF). Protein levels of PHD2, HIF-1alpha;, and VEGF were detected using Western blot. Results Compared with the control group, theCoCl2 induced hypoxic group showed decreased mRNA and protein levels of PHD2 (t=3.734, 3.122;P＜0.05), while those of HIF-1alpha; and VEGF increased (HIF-1alpha; mRNA:t=4.589,P＜0.05; HIF-1alpha; protein:t=3.778,P＜0.05. VEGF mRNA:t=3.926,P＜0.05; VEGF protein:t=3.257,P＜0.05). Compared with theCoCl2 induced hypoxic group, 50, 100, 200 mu;mol/L TMP treated groups showed increased mRNA and protein levels of PHD2 (PHD2 mRNA: t=3.286, 3.617, 3.886;P＜0.05. PHD2 protein: t=2.813, 3.026, 3.078; P＜0.05); while those of VEGF decreased (VEGF mRNA: 50 mu;mol/L TMP: t=1.696,P＞0.05; 100 mu;mol/L TMP:t=2.974,P＜0.05; 200 mu;mol/L TMP: t=3.492,P＜0.05; VEGF protein: 50 mu;mol/L TMP: t=1.986,P＞0.05; 100 mu;mol/L TMP: t=2.976,P＜0.05; 200 mu;mol/L TMP:t=3.136,P＜0.05); although changes in HIF-1alpha;mRNA levels were not statistically significant (t=1.025, 0.726, -1.386;P＞0.05), showed a decrease in HIF-1alpha;protein levels (50 mu;mol/L TMP: t=2.056,P＞0.05; 100 mu;mol/L TMP:t=3.058,P＜0.05; 200 mu;mol/L TMP:t=3.828,P＜0.05). ConclusionIn HUVECs, TMP can upregulate the mRNA and protein expression of PHD2, while down regulating HIF-1alpha; protein expression and VEGF mRNA and protein expression under acute hypoxic conditions.
