The acrosome reaction is a prerequisite for fertilization, and its signaling pathway has been investigated for decades. Regardless of the type of inducers present, the acrosome reaction is ultimately mediated by the elevation of cytosolic calcium. Inositol 1,4,5-trisphosphate-gated calcium channels are important components of the acrosome reaction signaling pathway and have been confirmed by several researchers. In this study, we used a novel permeabilization tool BioPORTER^® and first demonstrated its effectiveness in spermatozoa. The inositol 1,4,5-trisphosphate type-1 receptor antibody was introduced into spermatozoa by BioPORTER^® and significantly reduced the calcium influx and acrosome reaction induced by progesterone, solubilized zona pellucida, and the calcium ionophore A23187. This finding indicates that the inositol 1,4,5-trisphosphate type-1 receptor antibody is a valid inositol 1,4,5-trisphosphate receptor inhibitor and provides evidence of inositol 1,4,5-trisphosphate-gated calcium channel involvement in the acrosome reaction in human spermatozoa. Moreover, we demonstrated that the transfer of 1,4,5-trisphosphate into spermatozoa induced acrosome reactions, which provides more reliable evidence for this process. In addition, by treating the spermatozoa with inositol 1,4,5-trisphosphate/BioPORTER^® in the presence or absence of calcium in the culture medium, we showed that the opening of inositol 1,4,5-trisphosphate-gated calcium channels led to extracellular calcium influx. This particular extracellular calcium influx may be the major process of the final step of the acrosome reaction signaling pathway.
Acrosome Reaction/physiology* ; Calcimycin/pharmacology* ; Calcium/pharmacology* ; Calcium Ionophores/pharmacology* ; Drug Delivery Systems ; Humans ; Inositol 1,4,5-Trisphosphate Receptors/metabolism* ; Male ; Progesterone/pharmacology* ; Spermatozoa/metabolism* ; Zona Pellucida/metabolism*

To interact with the egg, the spermatozoon must undergo several biochemical and motility modifications in the female reproductive tract, collectively called capacitation. Only capacitated sperm can undergo acrosomal exocytosis, near or on the egg, a process that allows the sperm to penetrate and fertilize the egg. In the present study, we investigated the involvement of cyclic adenosine monophosphate (cAMP)-dependent processes on acrosomal exocytosis. Inhibition of protein kinase A (PKA) at the end of capacitation induced acrosomal exocytosis. This process is cAMP-dependent; however, the addition of relatively high concentration of the membrane-permeable 8-bromo-cAMP (8Br-cAMP, 0.1 mmol l^-1) analog induced significant inhibition of the acrosomal exocytosis. The induction of acrosomal exocytosis by PKA inhibition was significantly inhibited by an exchange protein directly activated by cAMP (EPAC) ESI09 inhibitor. The EPAC selective substrate activated AE at relatively low concentrations (0.02-0.1 μmol l^-1), whereas higher concentrations (>5 μmol l^-1) were inhibitory to the AE induced by PKA inhibition. Inhibition of PKA revealed about 50% increase in intracellular cAMP levels, conditions under which EPAC can be activated to induce the AE. Induction of AE by activating the actin severing-protein, gelsolin, which causes F-actin dispersion, was inhibited by the EPAC inhibitor. The AE induced by PKA inhibition was mediated by phospholipase C activity but not by the Ca²⁺-channel, CatSper. Thus, inhibition of PKA at the end of the capacitation process induced EPAC/phospholipase C-dependent acrosomal exocytosis. EPAC mediates F-actin depolymerization and/or activation of effectors downstream to F-actin breakdown that lead to acrosomal exocytosis.
8-Bromo Cyclic Adenosine Monophosphate/pharmacology* ; Acrosome/metabolism* ; Acrosome Reaction/drug effects* ; Calcimycin/pharmacology* ; Cyclic AMP/metabolism* ; Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors* ; Exocytosis/drug effects* ; Guanine Nucleotide Exchange Factors/metabolism* ; Humans ; Male ; Protein Kinase Inhibitors/pharmacology* ; Signal Transduction/drug effects* ; Spermatozoa/metabolism* ; Thapsigargin/pharmacology*

Sinensetin, a pentamethoxyflavone, is known to exert various pharmacological activities including anti-angiogenesis, anti-diabetic and anti-inflammatory activities. However, its effects on the human mast cell - 1 (HMC-1) mediated inflammatory mechanism remain unknown. To explore the mediator and cellular inflammatory response of sinensetin, we examined its influence on phorbol 12-myristate 13-acetate (PMA) plus A23187 induced inflammatory mediator production in a human mast cell line. In this study, interleukin (IL)-6 production was measured using the enzyme-linked immunosorbent assay and reverse transcription polymerase chain reaction. Sinensetin inhibited PMA plus A23187 induced IL-6 production in a dose-dependent manner as well as IL-4, IL-5 and IL-8 mRNA expression. Furthermore, sinensetin inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation, suggesting that sinensetin inhibits the production of inflammatory mediators by blocking STAT3 phosphorylation. Moreover, sinensetin was found to inhibit nuclear factor kappa B activation. These findings suggest that sinensetin may be involved in the regulation of mast cell-mediated inflammatory responses.
Calcimycin ; Enzyme-Linked Immunosorbent Assay ; Humans* ; Interleukin-4 ; Interleukin-5 ; Interleukin-6* ; Interleukin-8 ; Interleukins ; Mast Cells* ; NF-kappa B* ; Phosphorylation ; Polymerase Chain Reaction ; Reverse Transcription ; RNA, Messenger ; STAT3 Transcription Factor ; Transducers*

Mast cells are primary mediators of allergic inflammation. Beta-1,3-glucan (BG) protects against infection and shock by activating immune cells. Activation of the BG receptor induces an increase in intracellular Ca2+, which may induce exocytosis. However, little is known about the precise mechanisms underlying BG activation of immune cells and the possible role of mitochondria in this process. The present study examined whether BG induced mast cell degranulation, and evaluated the role of calcium transients during mast cell activation. Our investigation focused on the role of the mitochondrial calcium uniporter (MCU) in BG-induced degranulation. Black mouse (C57) bone marrow-derived mast cells were stimulated with 0.5 microg/ml BG, 100 microg/ml peptidoglycan (PGN), or 10 microM A23187 (calcium ionophore), and dynamic changes in cytosolic and mitochondrial calcium and membrane potential were monitored. BG-induced mast cell degranulation occurred in a time-dependent manner, and was significantly reduced under calcium-free conditions. Ruthenium red, a mitochondrial Ca2+ uniporter blocker, significantly reduced mast cell degranulation induced by BG, PGN, and A23187. These results suggest that the mitochondrial Ca2+ uniporter has an important regulatory role in BG-induced mast cell degranulation.
Animals ; Calcimycin ; Calcium* ; Cytosol ; Exocytosis ; Inflammation ; Ion Transport* ; Mast Cells* ; Membrane Potentials ; Mice* ; Mitochondria ; Peptidoglycan ; Ruthenium Red ; Shock

OBJECTIVETo investigate the pathogenesis of globozoospermia, fertilization ability of round-headed sperm, and the application value of assisted oocyte activation in intracytoplasmic sperm injection (ICSI) for the wives of glohozoospermia men.

METHODSWe collected oocytes from the wives of 2 globozoospermia patients and randomly divided them into two groups after ICSI to receive calcium ionophore A23187-activation and conventional treatment, respectively. We reviewed the relevant literature published at home and abroad, and discussed the etiology of globozoospermia, fertilization ability of round-headed sperm, and treatment options for this disease.

RESULTSQuality embryos were obtained in the A23187-activation group while no fertilized oocytes, oocyte cleavage, quality embryos, or blastular formation were found in the conventional treatment group. Both women achieved pregnancy and gave birth to healthy neonates after transfer of the quality embryos from the A23187-activation group.

CONCLUSIONCalcium ionophore A23187 can be applied to ICSI for the wives of globozoospermia men and bring about desirable clinical outcomes. Meanwhile, attention should be paid to its safety.

Calcimycin ; therapeutic use ; Calcium Ionophores ; therapeutic use ; Female ; Humans ; Infertility, Male ; drug therapy ; Male ; Oocytes ; Pregnancy ; Sperm Injections, Intracytoplasmic ; Spermatozoa ; abnormalities

Swiprosin-1 exhibits the highest expression in CD8+ T cells and immature B cells and has been proposed to play a role in lymphocyte biology through actin remodeling. However, regulation of swiprosin-1 gene expression is poorly understood. Here we report that swiprosin-1 is up-regulated in T cells by PKC pathway. Targeted inhibition of the specific protein kinase C (PKC) isotypes by siRNA revealed that PKC-theta is involved in the expression of swiprosin-1 in the human T cells. In contrast, down-regulation of swiprosin-1 by A23187 or ionomycin suggests that calcium-signaling plays a negative role. Interestingly, swiprosin-1 expression is only reduced by treatment with NF-kappaB inhibitors but not by NF-AT inhibitor, suggesting that the NF-kappaB pathway is critical for regulation of swiprosin-1 expression. Collectively, these results suggest that swiprosin-1 is a PKC-theta-inducible gene and that it may modulate the late phase of T cell activation after antigen challenge.
Actins ; Biology ; Calcimycin ; Down-Regulation ; Gene Expression ; Humans ; Ionomycin ; Lymphocytes ; NF-kappa B ; Precursor Cells, B-Lymphoid ; Protein Kinase C ; Protein Kinases ; RNA, Small Interfering ; T-Lymphocytes

OBJECTIVECheongseoikki-tang (CIT, Korean), also called Qingshu Yiqi decoction () and Seisho-ekki-to (Japanese), is well known as an effective traditional combination of herbs for treating cardiovascular diseases. This study was to research its effects on bone marrow-derived mast cell (BMMC)-mediated allergy and inflammation mechanisms.

METHODSIn this study, the biological effect of Cheongseoikki-tang ethanol extract (CITE) was evaluated, focusing on its effects on the production of allergic mediators by phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-stimulated BMMCs. These allergic mediators included interleukin-6 (IL-6), prostaglandin D2 (PGD2), leukotriene C4 (LTC4), and β-hexosaminidase (β-hex).

RESULTSOur data revealed that CITE inhibited the production of IL-6, PGD2, LTC4, and β-hex induced by PMA plus A23187 (P<0.05).

CONCLUSIONThese findings indicate that CITE has the potential for use in the treatment of allergy.

Animals ; Anti-Inflammatory Agents ; pharmacology ; therapeutic use ; Bone Marrow Cells ; pathology ; Calcimycin ; pharmacology ; Cell Degranulation ; drug effects ; Cell Survival ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Hypersensitivity ; drug therapy ; pathology ; Interleukin-6 ; secretion ; Leukotriene C4 ; pharmacology ; Male ; Mast Cells ; drug effects ; pathology ; physiology ; Mice ; Mice, Inbred BALB C ; Prostaglandin D2 ; biosynthesis ; Tetradecanoylphorbol Acetate ; pharmacology ; beta-N-Acetylhexosaminidases ; metabolism

Emodin, a naturally occurring anthraquinone derivative isolated from Polygoni cuspidati radix, has several beneficial pharmacologic effects, which include anti-cancer, anti-diabetic, and anti-inflammatory activities. In this study, the authors examined the effect of emodin on the production of proinflammatory cytokines, such as, tumor necrosis factor (TNF)-alpha and interleukin (IL)-6, in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the mechanism responsible for the regulation of pro-inflammatory cytokine production by emodin, the authors assessed its effects on the activations of transcriptional factor nuclear factor-kappaB (NF-kappaB) and mitogen-activated protein kinases (MAPKs). Emodin attenuated the nuclear translocation of (NF)-kappaB p65 and its DNA-binding activity by reducing the phosphorylation and degradation of IkappaBalpha and the phosphorylation of IkappaB kinase B (IKK). Furthermore, emodin dose-dependently attenuated the phosphorylations of MAPKs, such as, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase, and the stress-activated protein kinases (SAPK)/c-Jun-N-terminal kinase (JNK). Taken together, the findings of this study suggest that the anti-inflammatory effects of emodin on PMA plus A23187-stimulated BMMCs are mediated via the inhibition of NF-kappaB activation and of the MAPK pathway.
Animals ; Calcimycin* ; Calcium ; Cytokines ; Emodin* ; I-kappa B Kinase ; Interleukin-6* ; Interleukins ; Mast Cells* ; Mice ; Mitogen-Activated Protein Kinases ; NF-kappa B* ; p38 Mitogen-Activated Protein Kinases ; Phosphorylation ; Phosphotransferases* ; Protein Kinases ; Tumor Necrosis Factor-alpha*

We studied medium alkalinization in Salvia miltiorrhiza suspension cultures treated with salicylic acid and the effect of Ca2+ in this process through application of calcium channel antagonists (Verapamil, LaCl3, LiCl, 2-APB) and ionophore A23187. The results show that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture. Verapamil and LaCl3 or LiCl and 2-APB, two different groups of calcium channel antagonist, significantly inhibited the medium alkalinization induced by salicylic acid. However, the suppression effect of verapamil or LaCl3 on medium alkalinization induced by salicylic acid was higher than that of LiCl or 2-APB. When two types of calcium channel inhibitor (LaCl3 and 2-APB) were used together, the medium alkalinization induced by salicylic acid was completely suppressed and even reduced the pH in medium. On the other hand, A23187 could promote the medium alkalinization. Based on the results above, we speculated that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture, depending on the calcium from both extracell and intracell. Moreover, calcium from extracell plays a more dominant role in this process. Reveal of relationship in this research between Ca2+ and medium alkalinization can provide theory evidence for mechanism of the plant secondary metabolism.
Calcimycin ; pharmacology ; Calcium ; chemistry ; Calcium Channel Blockers ; pharmacology ; Calcium Ionophores ; pharmacology ; Cell Culture Techniques ; Culture Media ; chemistry ; Salicylic Acid ; pharmacology ; Salvia miltiorrhiza ; metabolism ; Verapamil ; pharmacology

OBJECTIVETo investigate the effects of endothelial microvesicles (EMVs) induced by calcium ionophore A23187 on H9c2 cardiomyocytes.

METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with 10 micromol/L A23187 for 30 min. EMVs from HUVECs were isolated by ultracentrifugation from the conditioned culture medium. EMVs were characterized using 1 and 2 microm latex beads and anti-PE-CD144 antibody by flow cytometry. For functional research, EMVs at different concentrations were cocultured with H9c2 cardiomyocytes for 6 h. Cell viability of H9c2 cells and the activity of LDH leaked from H9c2 cells were tested by colorimetry. Moreover, apoptosis of H9c2 cells was observed through Hoechst 33258 staining and tested by FITC-Annexin V/PI double staining.

RESULTSEMVs were induced by A23187 on HUVECs, and isolated by ultracentrifugation. We identified the membrane vesicles (< 1 microm) induced by A23187 were CD144 positive. In addition, the EMVs could significantly reduce the viability of H9c2 cells, and increase LDH leakage from H9c2 cells in a dose dependent manner (P < 0.05). Condensed nuclei could be observed with the increasing concentrations of EMVs through Hoechst 33258 staining. Furthermore, increased apoptosis rates of H9c2 cells could be assessed through FITC-Annexin V/PI double staining by flow cytometry.

CONCLUSIONMicrovesicles could be released from HUVECs after induced by A23187 through calcium influx, and these EMVs exerted a pro-apoptotic effect on H9c2 cells by induction of apoptosis.

Annexin A5 ; Apoptosis ; Calcimycin ; pharmacology ; Calcium ; metabolism ; Cell Line ; Cell Membrane ; drug effects ; Coculture Techniques ; Flow Cytometry ; Fluorescein-5-isothiocyanate ; analogs & derivatives ; Human Umbilical Vein Endothelial Cells ; Humans ; Myocytes, Cardiac ; drug effects ; Staining and Labeling