Effect of lappaconitine on neuropathic pain mediated by retrograde transport of P2X3 receptor in dorsal root ganglion neurons of rats with chronic constriction injury of the sciatic nerve / 中华创伤杂志

Objective:To investigate the effect of lappaconitine (LA) on neuropathic pain (NPP) mediated by retrograde transport of purinergic P2X3 receptor (P2X3R) in dorsal root ganglion (DRG) neurons of rats with chronic constriction injury (CCI) of the sciatic nerve.Methods:Seventy-two male healthy SD rats were selected to construct the NPP model following CCI of the sciatic nerve by ligating the right sciatic nerve. according to the random number table method. The rats were divided into CCI group, CCI+LA group and normal control group according to the random number table method, with 24 rats in each group. In normal control group, the right sciatic nerve was exposed without ligation. In CCI+LA group, the rats were given 2 g/L LA (ie, 4 mg/kg intravenously for once a day for one day only) after the same treatment as CCI group. Other two groups were injected with the identical amount of normal saline in the same way. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were evaluated before injury and at 2, 6, 12 and 24 hours after injury to evaluate the symptoms of neuralgia caused by nerve injury. The proximal and distal nerve fragments were collected in the three groups at 2, 6, 12 and 24 hours after injury. Western blotting was applied to analyze the expression of P2X3R at 2, 6, 12 and 24 hours after injury and the expression of neurotrophic factor (NGF) and tyrosine kinase receptor A (TrkA) at 24 hours after injury to evaluate the effect of LA on P2X3R, NGF and TrkA.Results:There were insignificant differences in MWT and TWL among all groups before injury (all P>0.05). Compared with normal control group, MWT and TWL were significantly decreased in CCI group and CCI+LA group at 2, 6, 12 and 24 hours after injury (all P<0.05 or 0.01). There were insignificant differences in MWT and TWL between CCI group and CCI+LA group at 2 and 6 hours after injury (all P>0.05), while MWT and TWL were significantly higher in CCI+LA group than those in CCI group at 12 and 24 hours after injury (all P<0.05 or 0.01). In the proximal sciatic nerve segment, Western blotting showed similar levels of P2X3R among all groups at 2, 6, 12 and 24 hours after injury (all P>0.05). In the distal sciatic nerve segment, Western blotting showed higher expression of P2X3R in CCI group than that in normal control group at 2, 6, 12, 24 hours after injury (all P<0.01), higher expression of P2X3R in CCI+LA group than that in normal control group at 2, 6 and 12 hours after injury (all P<0.05), similar expression of P2X3R expression between CCI+LA group and normal control group at 24 hours after injury ( P>0.05), similar expression of P2X3R between CCI group and CCI+LA group at 2 and 6 hours after injury (all P>0.05), and lower expression of P2X3R in CCI+LA group than that in CCI group at 12 and 24 hours after injury ( P<0.05 or 0.01). In the proximal and distal nerve fragments, the expression of NGF was lower in normal control group than that in CCI group and CCI+LA group ( P<0.05 or 0.01), but was similar between CCI group and CCI+LA group at 24 hours after injury ( P>0.05). In the proximal and distal nerve fragments, there were insignificant differences in the expression of TrkA among all groups at 24 hours after injury (all P>0.05). Conclusion:Early LA treatment after injury can alleviate mechanical and thermal hyperalgesia in NPP rats, which may be related to the reduction of P2X3R retrograde transport in DRG neuron axonal.

Effects of psychotherapy combined with early comprehensive rehabilitation therapy on cerebral infarction / 中国基层医药

Objective:To investigate the clinical efficacy of psychotherapy combined with early comprehensive rehabilitation therapy in the treatment of acute cerebral infarction and the possible mechanism of action.Methods:Eighty-four patients with acute cerebral infarction who received treatment in Yuhang Fifth People's Hospital, China between June 2018 and February 2020 were included in this study. They were randomly divided into an observation group ( n = 44) and a control group ( n = 40). The control group was treated with conventional therapy. The observation group was subjected to early comprehensive rehabilitation therapy combined with psychotherapy based on conventional therapy. All patients were treated for 1 month. Clinical efficacy, the percentage of highly glycosylated type I transmembrane glycoprotein-positive cells and vascular endothelial growth factor receptor-2-positive cells (CD 34+KDR +) in monocytes, and serum level of stromal cell-derived factor-1α were compared between the observation and control groups. Results:After treatment, the scores of Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD) and National Institutes of Health Stroke Scale (NIHSS) were (16.4 ± 3.8) points, (17.9 ± 5.2) points, (3.56 ± 0.46) points, respectively, which were significantly lower than those in the control group [(23.4 ± 5.6) points, (23.7 ± 6.4) points, (5.39 ± 0.87) points, t = 7.896, 7.258, 6.935, all P < 0.05]. Barthel Index, Fugl-Meyer score, and Functional Independence Score in the observation group were (79.7 ± 20.8) points, (54.6 ± 17.2) points, (96.8 ± 8.5) points, respectively, which were significantly higher than those in the control group [(60.4 ± 17.6) points, (39.6 ± 14.8) points, (83.1 ± 9.7) points, t = 8.123, 7.251, 8.009, all P < 0.05]. After treatment, the percentage of CD34 +KDR + in monocytes and serum level of stromal cell-derived factor-1α in the observation group were (1.58 ± 0.19)% and (1.84 ± 0.11) μg/L, respectively, which were significantly higher than those in the control group [(0.73 ± 0.20)% and (1.34 ± 0.09) μg/L, t = 7.125, 6.983, both P < 0.05). Conclusion:Based on conventional treatment, psychotherapy combined with early rehabilitation treatment can improve the clinical efficacy in the treatment of acute cerebral infarction possibly through increasing the percentage of CD 34+KDR + in monocytes and the serum level of stromal cell-derived factor-1α.

The cytoplasmic region of <i>Plasmodium falciparum</i> SURFIN_4.2 is required for transport from Maurer’s clefts to the red blood cell surface

<b>Background</b>: <i>Plasmodium</i>, the causative agent of malaria, exports many proteinsto the surface of the infected red blood cell (iRBC) in order to modify ittoward a structure more suitable for parasite development and survival. Onesuch exported protein, SURFIN_4.2, from the parasite of humanmalignant malaria, <i>P. falciparum,</i> wasidentified in the trypsin-cleaved protein fraction from the iRBC surface, andis thereby inferred to be exposed on the iRBC surface. SURFIN_4.2 alsolocalize to Maurer’s clefts – parasite-derived membranous structures establishedin the RBC cytoplasm and tethered to the RBC membrane – and their role intrafficking suggests that they are a pathway for SURFIN_4.2 transportto the iRBC surface. It has not been determined the participation of proteindomains and motifs within SURFIN_4.2 in transport from Maurer’sclefts to the iRBC surface; and herein we examined if the SURFIN_4.2 intracellularregion containing tryptophan-rich (WR) domain is required for its exposure on theiRBC surface. <b>Results</b>: We generated two transgenic parasite lineswhich express modified SURFIN_4.2, with or without a part of the intracellularregion. Both recombinant SURFIN_4.2 proteins were exported to Maurer’sclefts. However, only SURFIN_4.2 possessing the intracellular region wasefficiently cleaved by surface treatment of iRBC with proteinase K. <b>Conclusions</b>: These results indicate that SURFIN_4.2is exposed on the iRBC surface and that the intracellular region containing WRdomain plays arole on the transport from Maurer’s clefts to the iRBC membrane.

The Cytoplasmic Region of <i>Plasmodium falciparum</i> SURFIN_4.2 Is Required for Transport from Maurer’s Clefts to the Red Blood Cell Surface

Background: <i>Plasmodium</i>, the causative agent of malaria, exports many proteins to the surface of the infected red blood cell (iRBC) in order to modify it toward a structure more suitable for parasite development and survival. One such exported protein, SURFIN_4.2, from the parasite of human malignant malaria, <i>P. falciparum</i>, was identified in the trypsin-cleaved protein fraction from the iRBC surface, and is thereby inferred to be exposed on the iRBC surface. SURFIN_4.2 also localize to Maurer’s clefts—parasite-derived membranous structures established in the RBC cytoplasm and tethered to the RBC membrane—and their role in trafficking suggests that they are a pathway for SURFIN_4.2 transport to the iRBC surface. It has not been determined the participation of protein domains and motifs within SURFIN_4.2 in transport from Maurer’s clefts to the iRBC surface; and herein we examined if the SURFIN_4.2 intracellular region containing tryptophan-rich (WR) domain is required for its exposure on the iRBC surface. Results: We generated two transgenic parasite lines which express modified SURFIN_4.2, with or without a part of the intracellular region. Both recombinant SURFIN_4.2 proteins were exported to Maurer’s clefts. However, only SURFIN_4.2 possessing the intracellular region was efficiently cleaved by surface treatment of iRBC with proteinase K. Conclusions: These results indicate that SURFIN_4.2 is exposed on the iRBC surface and that the intracellular region containing WR domain plays a role on the transport from Maurer’s clefts to the iRBC membrane.

Arginine-glycine-aspartic acid-and RNase A-conjugated CdTe quantum dot-based nanoprobes for active targeting of human A375 malignant melanoma cells in vitro / 中华皮肤科杂志

Objective To prepare arginine-glycine-aspartic acid (RGD)-and ribonuclease A (RNase A)-conjugated CdTe quantum dot (QD) nanoprobes,and to observe their capability to target human A375 malignant melanoma cells.Methods RNase A-modified CdTe quantum dots (CdTe RQDs) were obtained by using a microwave-based heating method,and then chemically conjugated to the RGD peptide to prepare RGD-CdTe RQD nanoprobes,which were then physically and chemically characterized by transmission electron microscopy,powder crystal diffraction,fluorescence spectrophotometry,and ultraviolet absorption spectrophotometry.A375 cells were cultured in vitro and incubated with various concentrations (20,40,80 nmol/L) of RGD-CdTe RQD nanoprobes for different durations (12,24,36,72 hours).Then,methyl thiazolyl tetrazolium (MTT) assay was conducted to estimate the proliferative activity of A375 cells.To observe the targeting capability of RGD-CdTe RQD nanoprobes,A375 cells were treated with RGD-CdTe RQD nanoprobes at the concentration determined by MTT assay for one hour followed by laser confocal microscopy.Results CdTe RQDs with good dispersion and biocompatibility were obtained by using a microwave-based heating method,and then successfully conjugated to the RGD peptide to form RGD-CdTe RQD nanoprobes.The treatment with RGD-CdTe RQDs of 20 nmol/L for 12 hours exhibited the weakest effect on the proliferative activity of A375 cells,and hence,20 nmol/L was selected for the fluorescence imaging assay.Laser confocal microscopy revealed that RGD-CdTe RQD nanoprobes were able to actively target A375 cells.Conclusion RGD-CdTe RQD nanoprobes with a favorable capability to actively target A375 cells are successfully prepared in this study.

Changes in trafficking of GluR1-containing AMPA receptor and GluR2-containing AMPA receptor from cytoplasm to cell membrane in spinal dorsal horn in a rat model of incisional pain / 中华麻醉学杂志

Objective To investigate the changes in trafficking of GluRl-containing AMPA (GluR1-AMPA) receptor and GluR2-AMPA receptor from cytoplasm to cell membrane in the spinal cord dorsal horn in a rat model of incisional pain.Methods Thirty-two adult male SD rats aged 6-8 weeks weighing 280-300 g were randomly divided into 2 groups:control group (group C,n =8) and incisional pain group (group Ⅰ,n =24).An 1 cm long incision was made in the plautar surface of right hindpaw according to Brennan et al.in group Ⅰ.Cumulative pain score (CPS) and paw-withdrawal threshold to yon Frey stimuli (PWT) were measured at 3 h and day 1 and 3 afar incision ( T1,2,3 ).The animals were sacrificed after pain behavior assessment.Their lumbar segments of the spinal cord (L3-6) were removed.The expression of GluR1 and GluR2 in cell membrane and cytoplasm in spinal cord dorsal horn was determined by Western blot analysis.The co-expression of Stargazing with GluR1 and GluR2 in the spinal cord dorsal horn was examined by co-immuno-precipitation.Results The CPS was increased and PWT decreased; the GluR1 expression in cytoplasm was decreased while the expression of GluR1 in cell membrane and the co-expression of Stargazing with GluR1 were up-regulated in group Ⅰ as compared with group C.There was no significant change in the expression of GluR2 in cytoplasm and cell membrane and the co-expression of Stargazing with GluR2 in group Ⅰ as compared with group C.Conclusion GluR1-AMPA receptor transfers from cytoplasm to cell membrane but GluR2-AMPA receptor does not in rats with incisional pain.

Membrane Trafficking of Collecting Duct Water Channel Protein AQP2 Regulated by Akt/AS160

Akt (protein kinase B (PKB)) is a serine/threonine kinase that acts in the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. The PI3K/Akt signaling pathway, triggered by growth factors and hormones including vasopressin, is an important pathway that is widely involved in cellular mechanisms regulating transcription, translation, cell growth and death, cell proliferation, migration, and cell cycles. In particular, Akt and Akt substrate protein of 160 kDa (AS160) are likely to participate in the trafficking of aquaporin-2 (AQP2) in the kidney collecting duct. In this study, we demonstrated that 1) small interfering RNA (siRNA)-mediated gene silencing of Akt1 significantly decreased Akt1 and phospho-AS160 protein expression; and 2) confocal laser scanning microscopy of AQP2 in mouse cortical collecting duct cells (M-1 cells) revealed AS160 knockdown by siRNA increased AQP2 expression in the plasma membrane compared with controls, despite the absence of dDAVP stimulation. Thus, the results suggest that PI3K/Akt pathways could play a role in AQP2 trafficking via the AS160 protein.

Functions of intracytoplasmic connexin in tumor progression / 肿瘤研究与临床

A considerable amount of evidence established that gap junctional intercellular communication (GJIC) suppresses tumor development by halting the stage of tumor promotion.Consistently,GJIC is downregulated in tumors.The downregulation of GJIC is caused by not only the reduced expression level of connexin proteins but also their aberrant cytoplasmic localization.Although it has been thought long that cytoplasmic localization of conncxin proteins is merely one of the mechanisms of the downregu]ation of GJIC,careful studies with human tumor samples indicated that the expression level of intracytoplasmic connexin proteins had different biological functions.

Tissue-specific expression and subcellular localization of ALADIN, the absence of which causes human triple A syndrome

Triple A syndrome is a rare genetic disorder caused by mutations in the achalasia-addisonianism-alacrima syndrome (AAAS) gene which encodes a tryptophan aspartic acid (WD) repeat-containing protein named alacrima-achalasia-adrenal insufficiency neurologic disorder (ALADIN). Northern blot analysis shows that the 2.1 kb AAAS mRNA is expressed in various tissues with stronger expression in testis and pancreas. We show that human ALADIN is a protein with an apparent molecular weight of 60 kDa, and expressed in the adrenal gland, pituitary gland and pancreas. Furthermore, biochemical analysis using anti-ALADIN antibody supports the previous finding of the localization of ALADIN in the nuclear membrane. The mutations S544G and S544X show that alteration of S544 residue affects correct targeting of ALADIN to the nuclear membrane.

Detection of homodimer formation of CD99 through extracelluar domain using bimolecular fluorescence complementation analysis

Although various functions of CD99 have been reported, such as apoptosis and homotypic aggregation of thymocyte and transendothelial migration of immune cells, biochemical/molecular natures of CD99 are still elusive. Using mouse CD99 gene, we show that CD99 forms homodimer through its extracellular domain. Expression of mouse CD99 is up-regulated on T cells after CD3-mediated activation, like the case for human CD99. The potential of CD99 to form homodimer was tested with a recently developed bimoleular fluorescence complementation analysis (BiFC). In BiFC analysis, the dimerization-induced fluorescence was strong near the perinuclear region and was faded at the cell membrane. However, surface expression of CD99 was still detected by flow cytometry, suggesting that CD99 either in monomer form or in association with other molecules exists on the cell surface. In BiFC analysis using CD99 mutants with its extracellular, transmembrane, or cytosolic domains changed to corresponding human CD4 domains, the mutant replaced with human CD4-extracellular domain did not produce fluorescence. Purified soluble CD99-Fc fusion proteins bound to CD99-Fc immobilized onto the gold sensor chip in surface plasmon resonance analysis, confirming that the extracellular domain was responsible for dimer formation. Intracytoplasmic staining for CD99 expression in the thymocytes and mature T cells showed that most of the cells, even the cells with low surface level of CD99, contained the molecule inside the cell. Our results suggest that majority of CD99 homodimers may exit in the cell and be exported to the cell surface, dissociating from each other, after a certain regulatory signal is delivered.

The centrosomal localization of KM-HN-1 (MGC33607) depends on the leucine zipper motif and the C-terminal coiled-coil domain

KM-HN-1 is a C-terminal coiled-coil domain containing protein previously referred to as image clone MGC33607. This protein has been previously identified as a cancer/testis antigen and reported as nuclear and chromatin localizing protein. We raised polyclonal antisera with the GST fusion protein and identified them as a 105 kDa protein. Motif analysis showed that this protein harbors the leucine zipper motif in internal 1/3 region and the coiled-coil domain in the C-terminal region. Using the full length and various deletion mutants, we determined the motif that governs the subcellular localization of KM-HN-1. Immunofluorescence staining of the endogenous KM-HN-1 and various kinds of GFP-tagged KM-HN-1 revealed that KM-HN-1 localizes to the centrosomes as well as nucleus. The centrosomal localization-determining region of this protein is C-terminal coiled-coil domain in which the leucine zipper motif and the nuclear export signal (NES) harbor.

Effects of alcoholic extracts of seven traditional Chinese medicines and psoralen on tyrosinase in human YUGEN8 melanoma cell / 中华皮肤科杂志

Objective To explore the effects of alcoholic extracts of traditional Chinese medicines on the post-translational processing and trafficking of tyrosinase.Methods Human YUGEN8 amelanotic melanoma cells were grown in vitro;the cells were incubated with one of the seven traditional Chinese medicines,including Rhizoma Chuanxiong and psoralen.Protein analysis with Western blot,enzymolysis with endoglycosidase H (Endo H),and subcellular localization with laser confocal microscopy were per- formed.The expression,maturity and export from endoplasmic reticulum (ER) of tyrosinase in the treated cells were compared with those in the untreated controls.Results Compared with controls,an approximate- ly 80-kDa,Endo H-resistant tyrosinase doublet,which represented mature glycoform of tyrosinase,was in- creased in melanocytes treated with Semen Cuscutae,and in those treated with Semen Persicae.Within those cells,tyrosinase was distributed outside ER resident protein calnexin.Conclusion Both Semen Cus- cutae and Semen Persicae could induce tyrosinase maturation,stability and export from ER to distal site.

Cell-penetrating effects of HPV16E7_(49-57) epitope modified by peptide HIV-Tat_(49-57) / 中华皮肤科杂志

Objective To investigate the effects of the intracellular delivery of HPV16E7_(49-57) epi- tope modified by cell-penetrating peptide HIV-Tat_(49-57) and its influential factors.Methods The unique HLA-A2+/H-2kb+ limited CTL epitope of HPV16E7 fused with a cell-penetrating sequence (HIV-Tat_(49-57)) was designed and a 18-mer peptide was synthesized with aid of polypeptide solid phase synthesis technique. The intracellular transport capabilities of these peptides were tested with indirect immunofluorescence assay and laser confocal microscopy.In addition,the CTL epitope and 18-met peptide were used to stimulate PBMC of healthy C57BL/6 mice,and the E7_(49-57) specific CTL responses were measured by LDH cytotoxicity detection kit in PBMC of those mice.Results The HIV-Tat_(49-57) peptide could efficiently assist HPV 16E7_(49-57) peptide in penetrating into BHK cells in a time and dose-dependent manner (P＜0.05).Further- more,the specific CTL activity induced by the 18-mer peptide was much stronger than that induced by the single epitope.Conclusion The results show that HIV-Tat_(49-57) can efficiently deliver the exogenous anti- genic peptide into the cytoplasm of live cells,and induce specific CTL response.This is a new way to de- sign peptide-based vaccine of HPV.