Coexistence of Primary Sjögren's Syndrome and Autoimmune Gastritis With Pernicious Anemia and Subacute Combined Degeneration of the Spinal Cord: Case Report and Literature Review.

Background: Autoimmune gastritis (AIG) and Primary Sjögren's syndrome (pSS) are both autoimmune diseases with low prevalence in China. Subacute combined degeneration (SCD) of the spinal cord is the most common neurological manifestation of vitamin B12 deficiency. Until now, a patient with pSS and complications of AIG including SCD has not been reported. Case Presentation: A 69-year-old woman presented with palpitations and symmetrical and progressive numbness in her hands and feet. The patient had a sense of stepping on cotton and could not write or walk without help. We reviewed the patient's history and analyzed her blood tests, imaging, gastroscopic findings, and pathological results. The patient fulfilled the criteria of AIG, pSS, spinal cord SCD and early pernicious anemia (PA) simultaneously. Although pSS can lead to reduction of vitamin B12, this is the first overlapping case of pSS with spinal cord SCD. After symptomatic treatment, the patient returned to a normal life. Conclusions: This first report about the coexistence of pSS and complications of AIG including SCD and PA will promote a better understanding of the relationship between these diseases.

Expression of nerve growth factor carried by pseudotyped lentivirus improves neuron survival and cognitive functional recovery of post-ischemia in rats.

AIMS: Nerve growth factor (NGF) has been reported to prevent neuronal damage and contributes to the functional recovery in animal brain injury models and human ischemic disease as well. We aimed to investigate a potential therapeutic effect of NGF gene treatment in ischemic stroke and to estimate the functional recovery both at the cellular and cognitive levels in an ischemia rat model. METHODS: After microinjection of pseudolentivirus-delivered ß-NGF into an established ischemic stroke model in rats (tMCAO), we estimated neuronal cell apoptosis with TUNEL labeling and neurogenesis by cell proliferation marker Ki67 staining in both ischemic core and penumbra of striatum. Furthermore, we used behavioral functional tests, Morris water maze performance, to evaluate cognitive functional recovery in vivo and propose a potential underlying mechanism. RESULTS: We found that pseudolentivirus-mediated delivery of ß-NGF gene into the brain induced high expression in striatum of the infarct core area after ischemia in rats. The ß-NGF overexpression in the striatal infarction core after ischemia not only improved neuronal survival by reducing cell apoptosis and increasing cell proliferation, but also rescued cognitive functional impairment through upregulation of GAP-43 protein expression in tMCAO rat model of ischemia. CONCLUSION: This study demonstrates a potential ß-NGF gene therapy by utilization of pseudolentivirus in ischemia and indicates future applications of NGF gene treatment in ischemic patients.

Autophagy-mediated HMGB1 release promotes gastric cancer cell survival via RAGE activation of extracellular signal-regulated kinases 1/2.

High mobility group box-B1 (HMGB1), an autophagy activator, is crucial in tumorigenesis. However, its extracellular role and signaling in gastric cancer remain unclear. Samples were collected from gastric cancer patients and healthy controls. Immunohistochemistry and immunocytochemistry were used to determine the localization of HMGB1 in gastric cancer tissues, four gastric carcinoma cell lines (BGC-823, SGC-7901, MKN-28 and MKN-45) and a gastric epithelial cell line GES-1. Western blot analysis and ELISA were used to assess the effects of gefitinib, an epidermal growth factor receptor inhibitor, on autophagy and HMGB1 release in BGC-823 cells. MTT assay and western blot analysis assessed the effects of extracellular HMGB1 on cell proliferation and signaling transduction. Released HMGB1 promoted proliferation through activation of ERK1/2 MAPK. HMGB1 expression in gastric cancer tissues and serum was significantly increased compared to the controls and healthy serum. Gastric carcinoma cells showed an increased HMGB1 in the nuclei and cytoplasm, whereas GES-1 cells exhibited a lower HMGB1 with nuclear localization. Gefitinib increased autophagy and cytoplasmic HMGB1 release from the BGC-823 cells. Extracellular HMGB1 in autophagic cell supernatant promoted proliferation that was abolished by glycyrrhizic acid, an HMGB1 inhibitor. BGC-823 cells incubated with HMGB1 had increased ERK1/2 phosphorylation, while levels of JNK, p38 or AKT were not affected. Blocking RAGE­HMGB1 interaction with antibody or siRNA suppressed the ERK1/2 activation and gastric cancer cell growth, indicating that RAGE-mediated ERK1/2 signaling was necessary for tumor progression.

Effects of norepinephrine on immune functions of cultured splenic lymphocytes exposed to aluminum trichloride.

The aim of this study was to investigate the effect of norepinephrine (NE) on spleen lymphocytes exposed to aluminum trichloride (AlCl3). In this experiment, lymphocytes were isolated from spleens of healthy Wistar rats weighing about 130 g and cultured with RPMI-1640 medium containing the final concentration of 0.552 mmol/L AlCl3. NE was added to the cultured cells at the final concentrations of 0 (control group), 0.1 (low-dose group), 1 (mid-dose group), and 10 (high-dose group) nmol/L. No addition of both AlCl3 and NE serviced as blank (BG). The T lymphocyte proliferation; the contents of IL-2, TNF-α, and T lymphocyte subsets; immunoglobulin G (IgG) and intracellular cyclic adenosine monophosphate (cAMP) concentrations; and ß2-adrenergic receptor (ß2-AR) density were measured at the end of the culture. The result showed that NE decreased T lymphocyte proliferation and the contents of IL-2, TNF-α, and T lymphocyte subsets whereas increased the concentrations of IgG and intracellular cAMP and ß2-AR density of the lymphocyte exposed to AlCl3. AlCl3 exposure without adding NE showed the similar impacts on these measures compared with BG. The results suggested that NE aggravated AlCl3 immunotoxicity on the lymphocytes and disordered the immune functions of the lymphocyte through the ß2-AR-cAMP signal pathway.

Evidence that endogenous hydrogen sulfide exerts an excitatory effect on gastric motility in mice.

The present study was designed to investigate the effect of endogenous hydrogen sulfide (H2S) on gastric motility in mice. Western blotting and immunocytochemistry were used to determine expression levels of the H2S-producing enzymes cystathionine-ß-synthase (CBS) and cystathionine-γ-lyase (CSE) in gastric tissues and cultured smooth muscle cells. Physiological and intracellular recordings and the whole-cell patch clamp technique were used to evaluate the effect of H2S on the mechanical and electrical activities in muscle strips and in isolated smooth muscle cells, respectively. The results showed that CBS and CSE were expressed in mouse gastric smooth muscle. NaHS, a H2S donor, inhibited the amplitude and frequency of spontaneous contraction at high concentrations (>200 µM). However, NaHS at low concentrations (<100 µM) enhanced the basal tension and increased the contractile amplitude of muscle strips. This excitatory effect was not altered by the blockade of the enteric nerve with TTX, but was abolished by tetraethylammonium (TEA) or 4-aminopyridine (4-AP). Aminooxyacetic acid (AOA), but not propargylglycine (PAG), caused a concentration-dependent inhibition of spontaneous contraction. This effect was restored by L-cysteine and NaHS. In addition, NaHS at low concentrations (<100 µM) produced a depolarization of the membrane potential, whereas AOA hyperpolarized the membrane potential and decreased the amplitude of slow waves. Furthermore, AOA increased whole-cell delayed rectifier K⁺ current (I(K(V))). These findings suggest that endogenous H2S appears to be an excitatory gaseous mediator during physiological regulation of gastric motility and this excitable effect is mediated by depolarization of the membrane potential via inhibition of I(K(V)).

Excitatory regulation of angiotensin II on gastric motility and its mechanism in guinea pig.

In the present study, we investigated the effect of Ang II on gastric smooth muscle motility and its mechanism using intracellular recording and whole-cell patch clamp techniques. Ang II dose-dependently increased the tonic contraction and the frequency of spontaneous contraction in the gastric antral circular smooth muscles of guinea pig. ZD7155, an Ang II type 1 receptor (AT(1)R) blocker, completely blocked the effect of Ang II on the spontaneous contraction of gastric smooth muscle. In contrast, TTX, a sodium channel blocker, failed to block the effect. Furthermore, nicardipine, a voltage-gated Ca(2+)-channel antagonist, did not block the effect of Ang II on the tonic contraction of gastric smooth muscle, but external free-calcium almost completely blocked this effect. Both ryanodine, an inhibitor of calcium-induced Ca(2+) release (CICR) from ryanodine-sensitive calcium stores, and thapsigargin, which depletes calcium in calcium stores, almost completely blocked the effect of Ang II on tonic contraction. However, 2-APB, an inositol trisphosphate (IP(3)) receptor blocker, significantly, but not completely, blocked the Ang II effect on tonic contraction. We also determined that Ang II depolarized membrane potential and increased slow wave frequency in a dose-dependent manner. It also inhibited delayed rectifying potassium currents in a dose-dependent manner, but did not affect L-type calcium currents or calcium-activated potassium currents. These results suggest that Ang II plays an excitatory regulation in gastric motility via AT(1)R-IP(3) and the CICR signaling pathway. The Ang II-induced inhibition of delayed rectifying potassium currents that depolarize membrane potential is also involved in the potentiation of tonic contraction and the frequency of spontaneous contraction in the gastric smooth muscle of guinea pig.

The properties of spontaneous transient inward currents of interstitial cells in rabbit portal vein.

The present study was designed to investigate the properties of spontaneous transient inward currents generated by interstitial cells (ICs) in the rabbit portal vein. Single ICs were freshly isolated from smooth muscle of the rabbit portal vein enzymetically. Using whole-cell patch clamp techniques, the spontaneous transient inward currents (STICs) were recorded at -60 mV of holding potential in freshly dispersed ICs. Both gadolinium, a non-selective cation channel inhibitor, and niflumic acid, a calcium-activated chloride channel blocker, abolished the inward currents. Replacement of external Na(+) with N-methyl-d-glucamine (NMDG(+)) also blocked the inward currents. The inward currents were abolished by caffeine, carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP), thapsigargin and ryanodine, but were partly inhibited by 2-aminoethoxydiphenyl borate (2-APB). W-7, a calmodulin inhibitor, increased the amplitude of the inward currents. These results suggest that non-selective cation channels are involved in the generation of the spontaneous transient inward currents recorded from ICs. The currents are regulated by intracellular calcium and calmodulin. But in the present study, the involvement of the calcium-activated chloride channels in the generation of the currents cannot be excluded.

Spontaneous rhythmic inward currents recorded in interstitial cells of rabbit portal vein.

It is now well established that smooth muscle of the portal vein exhibits spontaneous rhythmic contraction in vitro. The present study was designed to investigate the pacemaking mechanism(s) underlying the spontaneous rhythmic contractions in the rabbit portal vein (RPV). Using whole-cell patch clamp techniques, spontaneous inward currents were recorded at -60 mV of holding potential in freshly dispersed c-Kit immunopositive interstitial cells (ICs) isolated from sections of RPV. The inward currents were abolished by caffeine, FCCP, thapsigargin, and ryanodine, but were partially inhibited by 2-APB. Both gadolinium, a non-selective cation channel inhibitor, and niflumic acid, a chloride channel blocker, inhibited the inward currents completely. Replacement of external Na(+) with NMDG(+) also blocked the inward currents. W-7, a calmodulin inhibitor, increased both the amplitude and frequency of the inward currents. Taken together, these results indicate that non-selective cationic channels are involved in the generation of spontaneous inward currents recorded from ICs. Intracellular calcium concentration and calmodulin regulate the spontaneous inward currents, which may account for spontaneous rhythmic contraction in the RPV, but a role of chloride channels may not be excluded in the present study.

Pacemaking activity is regulated by membrane stretch via the CICR pathway in cultured interstitial cells of Cajal from murine intestine.

Membrane stretch is an important stimulus in gastrointestinal (GI) motility regulation, but the relationship between membrane stretch and the pacemaking activity of GI smooth muscle is poorly understood. We examined the effect of intestinal distension on slow waves and the effect of membrane stretch on pacemaker currents in cultured intestinal interstitial cells of Cajal (ICCs) from murine small intestine. At organ level, intestinal distension significantly increased amplitude of slow and fast waves, and enhanced frequencies of fast but not slow waves. At the cellular level, membrane stretch-induced by hyposmotic cell swelling (MSHC) depolarized membrane potential and activated large inward holding current, but suppressed amplitude of pacemaker potential or pacemaking current. External Ca(2+)-free solution abolished pacemaker current and blocked MSHC-induced inward holding current. However, a sustained inward holding current was activated and the amplitude of pacemaker current was increased by high ethylene glycol tetraacetic acid (EGTA) in pipette. Then MSHC also potentiated the inward holding current. MSHC significantly increased amplitude of rhythmic Ca(2+) transients and basal intracellular Ca(2+) concentration ([Ca(2+)](i)). 2-APB blocked both pacemaker current and Ca(2+) transients but did not alter the effect of MSHC on pacemaker current and Ca(2+) transients. In contrast, ryanodine inhibited Ca(2+) transients but not pacemaker current, and completely blocked MSHC-induced inward holding current and MSHC-induced increase of basal [Ca(2+)](i). These results suggest that intestinal distension potentiates intestinal motility by increasing the amplitude of slow waves. Membrane stretch potentiates pacemaking activity via releasing Ca(2+) from calcium-induced calcium release (CICR) in cultured intestinal ICCs.

Actin microfilament involved in regulation of pacemaking activity in cultured interstitial cells of Cajal from murine intestine.

The present study investigated the effect of actin microfilament structure on pacemaker currents and calcium oscillation in cultured murine intestinal interstitial cells of Cajal (ICCs) by whole-cell patch-clamp technique and calcium imaging technique. Cytochalasin B, a disruptor of actin microfilaments, decreased the amplitude and frequency of pacemaker currents from 491.32 +/- 160.33 pA and 11.73 +/- 0.79 cycles/min to 233.12 +/- 92.00 pA and 10.29 +/- 0.76 cycles/min. Cytochalasin B also decreased the amplitude and frequency of calcium oscillation from 0.32 +/- 0.08 (DeltaF/F0) and 2.75 +/- 0.17 cycles/min to 0.02 +/- 0.01 (DeltaF/F0) and 1.20 +/- 0.08 cycles/min. Phalloidin, a stabilizer of actin microfilaments, increased the amplitude and frequency of pacemaker currents from 751.79 +/- 282.82 pA and 13.93 +/- 1.00 cycles/min to 1234.34 +/- 607.83 pA and 14.68 +/- 1.00 cycles/min. Phalloidin also increased the amplitude and frequency of calcium oscillation from 0.26 +/- 0.01 (DeltaF/F0) and 2.27 +/- 0.18 cycles/min to 0.43 +/- 0.03 (DeltaF/F0) and 2.87 +/- 0.07 cycles/min. 2-Aminoethoxydiphenyl borane (2-APB), an IP(3) receptor blocker, suppressed both pacemaker currents and calcium oscillations. 2-APB also blocked the phalloidin-induced increase in pacemaker currents and calcium oscillation. Ryanodine, an inhibitor of calcium-induced calcium release, did not affect pacemaker current but suppressed calcium oscillations. Ryanodine had no effect on altering phalloidin-induced increases in pacemaker current and calcium oscillation. These results suggest that actin microfilaments regulate pacemaker activity via the IP(3)-induced calcium release signaling pathway.

Atrial natriuretic peptide signal pathway upregulated in stomach of streptozotocin-induced diabetic mice.

AIM: To investigate atrial natriuretic peptide (ANP) secretion from gastric mucosa and the relationship between the ANP/natriuretic peptide receptor type A (NPR-A) pathway and diabetic gastroparesis. METHODS: Male imprinting control region (ICR) mice (4 wk old) were divided into two groups: control mice, and streptozotocin-induced diabetic mice. Eight weeks after injection, spontaneous gastric contraction was recorded by using physiography in control and streptozotocin-induced diabetic mice. The ANP-positive cells in gastric mucosa and among dispersed gastric epithelial cells were detected by using immunohistochemistry and flow cytometry, respectively. ANP and natriuretic peptide receptor type A (NPR-A) gene expression in gastric tissue was observed by using the reverse transcriptase polymerase chain reaction. RESULTS: The frequency of spontaneous gastric contraction was reduced from 12.9 +/- 0.8 cycles/min in the control group to 8.4 +/- 0.6 cycles/min in the diabetic mice (n = 8, P < 0.05). However, the amplitude of contraction was not significantly affected in the diabetic group. The depletion of interstitial cells of Cajal in the gastric muscle layer was observed in the diabetic mice. ANP-positive cells were distributed in the gastric mucosal layer and the density index of ANP-positive cells was increased from 20.9 +/- 2.2 cells/field in control mice to 51.8 +/- 2.9 cells/field in diabetic mice (n = 8, P < 0.05). The percentage of ANP-positive cells among the dispersed gastric epithelial cells was increased from 10.0% +/- 0.9% in the control mice to 41.2% +/- 1.0% in the diabetic mice (n = 3, P < 0.05). ANP and NPR-A genes were both expressed in mouse stomach, and the expression was significantly increased in the diabetic mice. CONCLUSION: These results suggest that the ANP/NPR-A signaling pathway is upregulated in streptozotocin-induced diabetic mice, and contributes to the development of diabetic gastroparesis.

Dual effect of exogenous hydrogen sulfide on the spontaneous contraction of gastric smooth muscle in guinea-pig.

Hydrogen sulfide (H(2)S) is produced endogenously in mammalian tissues and is important in both physiological and pathological processes. Despite its importance, little is known regarding the effect of H(2)S on gastrointestinal motility. We evaluated the effect of H(2)S on the spontaneous contraction of gastric antrum smooth muscle in the guinea pig (Cavia porcellus) using a physiograph. In addition, we investigated whether the effect of H(2)S was mediated by ionic channels by recording membrane currents in freshly dispersed gastric antrum myocytes using a whole-cell patch clamp. Sodium hydrogen sulfide (NaHS), an H(2)S donor, had a dual effect on the spontaneous contraction of gastric antrum muscle strips. At high concentrations (0.3-1.0 mM), NaHS suppressed the amplitude of spontaneous contraction. At low concentrations (0.1-0.3 mM), NaHS enhanced the resting tension of muscle strips while slightly reducing the contractile amplitude. The excitatory effect on spontaneous contraction, caused by low concentrations of NaHS, was abolished when the muscle strips were pretreated with 10 mM tetraethylammonium (TEA), a nonselective potassium channel blocker, or 0.5 mM 4-Aminopyridine (4-AP), a voltage-gated K(+) channel blocker. However, the excitatory effect of NaHS was not completely blocked by low concentrations of TEA (1 mM). Pretreatment with both TEA (1 mM) and 4-AP (0.5 mM) completely abolished the excitatory effect. The dose-response curve for the inhibitory effect of NaHS on the spontaneous contraction of gastric smooth muscle was shifted significantly to the left by TEA and 4-AP. Both Pinacidil, a K(ATP) channel opener, and NaHS significantly inhibited TEA-potentiated spontaneous contraction. Glibenclamide, a K(ATP) channel blocker, partially, but significantly, reversed the reduction in amplitude. NaHS enhanced the amplitude of the K(ATP) current, but inhibited the voltage-gated K(+) channel current (IK(V)) in a dose-dependent manner. NaHS had no effect on STOC at low concentrations (0.1-1.0 mM) but significantly inhibited STOC at high concentrations (4-10 mM). Our results suggest that H(2)S has multiple actions during the regulation of gastric motility in the guinea-pig. An excitatory effect is mediated via inhibition of the voltage-gated K(+) channel and an inhibitory effect is mediated via activation of the K(ATP) channel.