Upregulation of Phosphodiesterase 7A Contributes to Concurrent Pain and Depression via Inhibition of cAMP-PKA-CREB-BDNF Signaling and Neuroinflammation in the Hippocampus of Mice.

BACKGROUND: Phosphodiesterases (PDEs) are enzymes that catalyze the hydrolysis of cyclic adenosine monophosphate AMP (cAMP) and/or cyclic guanosine monophosphate (cGMP). PDE inhibitors can mitigate chronic pain and depression when these disorders occur individually; however, there is limited understanding of their role in concurrent chronic pain and depression. We aimed to evaluate the mechanisms of action of PDE using 2 mouse models of concurrent chronic pain and depression. METHODS: C57BL/6J mice were subjected to partial sciatic nerve ligation (PSNL) to induce chronic neuropathic pain or injected with complete Freund's adjuvant (CFA) to induce inflammatory pain, and both animals showed depression-like behavior. First, we determined the change in PDE expression in both animal models. Next, we determined the effect of PDE7 inhibitor BRL50481 or hippocampal PDE7A knockdown on PSNL- or CFA-induced chronic pain and depression-like behavior. We also investigated the role of cAMP-protein kinase A (PKA)-cAMP response element binding protein (CREB)-brain-derived neurotrophic factor (BDNF) signaling and neuroinflammation in the effect of PDE7A inhibition on PSNL- or CFA-induced chronic pain and depression-like behavior. RESULTS: This induction of chronic pain and depression in the 2 animal models upregulated hippocampal PDE7A. Oral administration of PDE7 inhibitor, BRL50481, or hippocampal PDE7A knockdown significantly reduced mechanical hypersensitivity and depression-like behavior. Hippocampal PDE7 inhibition reversed PSNL- or CFA-induced downregulation of cAMP and BDNF and the phosphorylation of PKA, CREB, and p65. cAMP agonist forskolin reversed these changes and caused milder behavioral symptoms of pain and depression. BRL50481 reversed neuroinflammation in the hippocampus in PSNL mice. CONCLUSIONS: Hippocampal PDE7A mediated concurrent chronic pain and depression in both mouse models by inhibiting cAMP-PKA-CREB-BDNF signaling. Inhibiting PDE7A or activating cAMP-PKA-CREB-BDNF signaling are potential strategies to treat concurrent chronic pain and depression.

Electroacupuncture Delays Cartilage Degeneration by Modulating Nuclear Factor-κB Signaling Pathway.

OBJECTIVE: To illustrate the molecular mechanisms underlying the therapeutic effects of electroacupuncture (EA) on knee osteoarthritis (OA). METHODS: Twenty-seven six-month-old New Zealand white rabbits were allocated into three groups in accordance with a random number table: normal group (no surgery-induced OA; without treatment), model group (surgery-induced OA; without treatment) and EA group [surgery-induced OA; received treatment with EA at acupoints Dubi (ST 35) and Neixiyan (EX-LE 5), 30 min twice a day]. After eight consecutive weeks of treatment, the histopathological alterations in cartilage were observed using optical microscopy and transmission electron microscopy, cartilage degeneration was evaluated by modified Mankin's score principles, the synovial fluid concentration of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-3 (MMP-3) were evaluated by enzyme-linked immunosorbent assay, and the protein expression levels of IL-1ß, IL-6, TNF-α, MMP-3, IκB kinase-ß (IKK-ß), nuclear factor of α light polypeptide gene enhancer in B-cells inhibitor α (IκB-α) and nuclear factor-κB (NF-κB) p65 were quantified by Western blot analysis. RESULTS: EA treatment significantly improved cartilage structure arrangement and reduced cellular degeneration. The IL-1ß, IL-6, TNF-α and MMP-3 of synovial fluid in the EA-treated group were significantly decreased compared with the model group (all P<0.01). Compared with the model group, the IL-1ß, IL-6, TNF-α, MMP-3, IKK-ß and NF-κB p65 protein expressions in cartilage of EA-treated group were significantly decreased (all P<0.01), whereas IκB-α expression was significantly up-regulated (P<0.01). CONCLUSION: EA treatment may delay cartilage degeneration by down-regulating inflammatory factors through NF-κB signaling pathway, which may, in part, explain its clinical efficacy in the treatment of knee OA.

Potential synergistic and multitarget effect of herbal pair Chuanxiong Rhizome-Paeonia Albifora Pall on osteoarthritis disease: a computational pharmacology approach.

OBJECTIVE: To study the polypharmacological mechanism of herbal pair Chuanxiong Rhizome-Paeonia Albifora Pall (HP CXR-PAP) on the treatment for osteoarthritis (OA). METHODS: Chemical space was used to discuss the similarities and differences between the molecule sets of HP CXR-PAP and drugs. Docking protocol was used to study the interaction between HP CXR-PAP and OA target enzymes. The similarities and differences of HP CXR-PAP and drugs in target spaces were elucidated by network features. RESULTS: The plots between the molecule sets of HP CXR-PAP and drugs in chemical space had the majority in the same region, and compounds from HP CXR-PAP covered a much larger additional region of space than drug molecules, which denoted the diverse structural properties in the molecule set of HP CXR-PAP. The molecules in HP CXR-PAP had the properties of promiscuous drugs and combination drug, and both HP CXR-PAP ligand-target interaction network and drug ligand-target interaction network were similar in the interaction profiles and network features, which revealed the effects of multicomponent and multitarget. CONCLUSION: The clue of potential synergism was obtained in curing OA disease by Chinese medicine, which revealed the advantages of Chinese medicine for targeting osteoarthritis disease.

Experimental study on the suppression of sodium nitroprussiate-induced chondrocyte apoptosis by Tougu Xiaotong Capsule (透骨消痛胶囊)-containing serum.

OBJECTIVE: To study the mechanism of action of Tougu Xiaotong Capsule (透骨消痛胶囊, TGXTC) ex vivo in suppressing chondrocyte (CD) apoptosis induced by sodium nitroprussiate (SNP). METHODS: Thirty New Zealand rabbits, 2 months old, were randomized by lottery into five groups, six in each: the blank group treated with saline, the positive control group treated with Zhuanggu Guanjie Pill (壮骨关节丸, 70 mg/kg), and the three experimental groups, EGA, EGB, and EGC, treated with low dose (35 mg/kg), moderate dose (70 mg/kg), and high dose (140 mg/kg) of TGXTC, respectively. All treatments were administered via gastrogavage twice a day for 3 days. Arterial blood was collected from the abdominal aorta and drug or drug metabolites-containing serum was prepared. CDs obtained from knee joints of 16 four-week-old New Zealand rabbits were cultured to the third passage and confirmed by toluidine blue staining. SNP of various final concentrations (0, 0.5, 1.0, and 2.0 mmol/L) was used to induce CD apoptosis, and the dosage-effect relationship of SNP in inducing CD apoptosis was determined. Serum samples from the blank, control, and three dosages of TGXTC-treated rabbits were tested in the CD culture in the presence of SNP. Cell apoptosis was determined by Hoechst 33342 staining, viability of CDs was quantified by MTT, CD apoptosis rate was determined by annexin V-FITC/PI staining, levels of p53 and Bcl-2 mRNA expression in CDs were determined with RT-PCR, and contents of caspase-3 and caspase-9 proteins were determined by colorimetry. RESULTS: CD apoptosis was induced by SNP at all concentrations tested and in a dose-dependent manner. The SNP concentration of 1 mmol/L and treatment duration of 24 h appeared to be optimal and were selected for the study. Serum samples from the positive control rabbits and from the two higher doses of TGXTC-treated rabbits showed reduction of SNP-induced CD apoptosis, decrease in p53 mRNA expression, inhibition of catalytic activities of caspase-3 and caspase-9, and increase in Bcl-2 mRNA expression when compared with the serum from the blank group (P<0.05). CONCLUSION: TGXTC-containing sera antagonized SNP-induced CD apoptosis and the molecular basis for the action was associated with up-regulation of Bcl-2, down-regulation of p53 expression, and inhibition of caspase-3 and caspase-9 catalytic activities.

Clinical study on the treatment of knee osteoarthritis of Shen-Sui insufficiency syndrome type by electroacupuncture.

OBJECTIVE: To study the clinical effificacy of electroacupuncture (EA) on treating knee osteoarthritis (KOA) of Shen ()-Sui () insuffificiency (SSI) syndrome type. METHODS: A total of 245 patients (279 knees) of KOA-SSI were randomly assigned to two groups by lottery: 141 knees in the treatment group and 138 knees in the control group. The treatment group was managed with EA at the dominant points of Neixiyan (Ex-LE4) and Waixiyan (Ex-LE5) as well as the conjugate points of Xuanzhong (GB39) and Taixi (KI3) for 30 min, once a day, with 15 days as one course; 2 courses were applied with a 5-day interval in between. The control group was treated with intra-articular injection of 2 mL hyaluronic acid into the affected joint every 7 days for 5 times in total. The clinical effects on the patients in different stages were observed, and their symptom scores of knee and contents of cytokines, including interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), prostaglandin E(2alpha) (PGE(2alpha)) and matrix metalloproteinases-3 (MMP-3), in the knee joint fluid were measured before and after treatment. RESULTS: The study was completed in 235 patients (263 knees); four patients (7 knees) in the treatment group and six patients (9 knees) in the control group dropped out. Comparison of therapeutic effects (excellent and effective rates) between the two groups showed insignificant differences (P>0.05). Symptom scores of knee and contents of cytokines in the knee flfluid after treatment were lowered signifificantly in the patients of stage I-III in both groups (P<0.05 or P<0.01). However, the lowering of the total symptom score of knee in the patients of stage III in the treatment group was more signifificant (P<0.05). CONCLUSIONS: EA could effectively alleviate the clinical symptoms in KOA patients of stage III, showing an effect superior to that of hyaluronic acid. EA also shows action in suppressing the secretion of IL-1, IL-6, TNF-alpha, PGE(2alpha) and MMP-3 in the knee flfluid.

Experimental study of millimeter wave-induced differentiation of bone marrow mesenchymal stem cells into chondrocytes.

Low power millimeter wave irradiation is widely used in clinical medicine. We describe the effects of this treatment on cultured mesenchymal stem cells (MSCs) and attempted to identify the underlying mechanism. Cells cultured using the whole marrow attachment culture method proliferated dispersedly or in clones. Flow cytometric analyses showed that the MSCs were CD90 positive, but negative for CD45. The negative control group (A) did not express detectable levels of Cbfa1 or Sox9 mRNA at any time point, while cells in the millimeter wave-induced groups (B and C) increasingly expressed both genes after the fourth day post-induction. Statistical analysis showed that starting on the fourth day post-induction, there were very significant differences in the expression of Cbfa1 and Sox9 mRNA between groups A and B as well as A and C at any given time point, between treated groups B and C after identical periods of induction, and within each treated group at different induction times. Transition electron microscopy analysis showed that the rough endoplasmic reticulum of cells in the induced groups was richer and more developed than in cells of the negative control group, and that the shape of cells shifted from long-spindle to near ellipse. Toluidine blue staining revealed heterochromia in the cytoplasm and extracellular matrix of cells in the induced groups, whereas no obvious heterochromia was observed in negative control cells. Induced cells also exhibited positive immunohistochemical staining of collagen II, in contrast to the negative controls. These results show that millimeter wave treatment successfully induced MSCs to differentiate as chondrocytes and the extent of differentiation increased with treatment duration. Our findings suggest that millimeter wave irradiation can be employed as a novel non-drug inducing method for the differentiation of MSCs into chondrocytes.

[Immunological screening for multiple myeloma-associated antigens and their bioinformatics analysis].

This study was aimed to screen the cell cDNA expression library of multiple myeloma HMy2 (MM HMy2) by using "serological analysis of cDNA expression library (SEREX)" technique. The obtained 30 positive clones were all sequenced, and analyzed by BLAST (basic local alignment search tool). The results indicated that 6 known genes and 12 new MM-associated genes were obtained, part of which sequences were spliced by EST (expressed sequence tag) splicing. 6 known genes such as for ring finger protein 167, KLF10, TPT1 protein, p02 protein, cDNA FLJ46859 fis, DNMT1 methyltrasferase etc. have been demonstrated a certain relationship with other tumor's formation, progress and prognosis. The structures and functions of the new genes preliminarily analyzed and predicted by means of bioinformatics showed that MMSA-3, MMSA-8 and MMSA-11 encoding 215, 160 and 122 amino acid residues respectively had the full open reading frames (ORF). All the new genes might be located at euchromosomes but MMSA-1 at sex chromosome. MMSA-4 was highly similar to the protein controlling the transcription of tumor antigen, MMSA-5 might take part in cell phagocytosis, MMSA-7 might inactivated NF-kappaB, and MMSA-12 might be a lymphocytic cytoplasmic protein. The specificity of new genes such as MMSA-3 and MMSA-7 were higher, by a preliminary analysis using CrELISA. It is concluded that tumor antigens screened by this study can be used for early immunological diagnosis, surveillance of minor residual foci, assessment of prognosis, and preparation of tumor vaccine and so on.