Photochemical Internalization of Etoposide Using Dendrimer Nanospheres Loaded with Etoposide and Protoporphyrin IX on a Glioblastoma Cell Line.

Glioblastoma multiforme (GBM) is the most common malignant primary neoplasm of the adult central nervous system originating from glial cells. The prognosis of those affected by GBM has remained poor despite advances in surgery, chemotherapy, and radiotherapy. Photochemical internalization (PCI) is a release mechanism of endocytosed therapeutics into the cytoplasm, which relies on the membrane disruptive effect of light-activated photosensitizers. In this study, phototherapy by PCI was performed on a human GBM cell-line using the topoisomerase II inhibitor etoposide (Etop) and the photosensitizer protoporphyrin IX (PpIX) loaded in nanospheres (Ns) made from generation-5 polyamidoamine dendrimers (PAMAM(G5)). The resultant formulation, Etop/PpIX-PAMAM(G5) Ns, measured 217.4 ± 2.9 nm in diameter and 40.5 ± 1.3 mV in charge. Confocal microscopy demonstrated PpIX fluorescence within the endo-lysosomal compartment, and an almost twofold increase in cellular uptake compared to free PpIX by flow cytometry. Phototherapy with 3 min and 5 min light illumination resulted in a greater extent of synergism than with co-administered Etop and PpIX; notably, antagonism was observed without light illumination. Mechanistically, significant increases in oxidative stress and apoptosis were observed with Etop/PpIX-PAMAM(G5) Ns upon 5 min of light illumination in comparison to treatment with either of the agents alone. In conclusion, simultaneous delivery and endo-lysosomal co-localization of Etop and PpIX by PAMAM(G5) Ns leads to a synergistic effect by phototherapy; in addition, the finding of antagonism without light illumination can be advantageous in lowering the dark toxicity and improving photo-selectivity.

Arecae pericarpium extract induces porcine lower-esophageal-sphincter contraction via muscarinic receptors.

BACKGROUND: Gastroesophageal reflux disease (GERD) is associated with lower esophageal sphincter (LES) incompetence. In some patients, GERD is refractory to acid reduction therapy which is the main treatment for GERD. So far, medications that can increase LES tone are few. Arecae pericarpium (A. pericarpium) is a medication in Traditional Chinese Medicine known to promote intestinal motility. METHODS: We investigated the effect of A. pericarpium extracts on porcine LES motility. In addition, we used tetrodotoxin (TTX) and atropine to study the underlying mechanism of A. pericarpium extracts-induced contractions of LES. RESULTS: The results of this study showed that A. pericarpium extracts and their main active ingredient, arecoline, can induce the contractions of porcine LES sling and clasp muscles in a dose-response manner. TTX did not have an inhibitory effect on the contractions induced by A. pericarpium extracts and arecoline in LES. However, atropine significantly inhibited A. pericarpium extracts- and arecoline-induced contractions of LES. CONCLUSION: A. pericarpium extracts can induce the contractions of porcine LES in a dose dependent manner, possibly through muscarinic receptors, and hence, may be worth developing as an alternative therapy for GERD.

Salvia miltiorrhiza Induces Tonic Contraction of the Lower Esophageal Sphincter in Rats via Activation of Extracellular Ca2+ Influx.

Up to 40% of patients with gastroesophageal reflux disease (GERD) suffer from proton pump inhibitor refractory GERD but clinically the medications to strengthen the lower esophageal sphincter (LES) to avoid irritating reflux are few in number. This study aimed to examine whether Salvia miltiorrhiza (SM) extracts induce tonic contraction of rat LES ex vivo and elucidate the underlying mechanisms. To investigate the mechanism underlying the SM extract-induced contractile effects, rats were pretreated with atropine (a muscarinic receptor antagonist), tetrodotoxin (a sodium channel blocker), nifedipine (a calcium channel blocker), and Ca(2+)-free Krebs-Henseleit solution with ethylene glycol tetraacetic acid (EGTA), followed by administration of cumulative dosages of SM extracts. SM extracts induced dose-related tonic contraction of the LES, which was unaffected by tetrodotoxin, atropine, or nifedipine. However, the SM extract-induced LES contraction was significantly inhibited by Ca(2+)-free Krebs-Henseleit solution with EGTA. Next, SM extracts significantly induce extracellular Ca(2+) entry into primary LES cells in addition to intracellular Ca(2+) release and in a dose-response manner. Confocal fluorescence microscopy showed that the SM extracts consistently induced significant extracellular Ca(2+) influx into primary LES cells in a time-dependent manner. In conclusion, SM extracts could induce tonic contraction of LES mainly through the extracellular Ca(2+) influx pathway.

Newly diagnosed dementia and increased risk of hemorrhagic stroke: A nationwide population-based study.

BACKGROUND: This retrospective cohort study was designed to assess whether there is an association between newly diagnosed dementia and the risk of stroke. METHODS: From Taiwan's National Health Insurance Research Database of reimbursement claims, we identified 2811 patients with newly diagnosed dementia and 14,055 randomly selected, age-matched patients without dementia. A Cox proportional hazards model was constructed to calculate the development of stroke, including ischemic stroke, and intracerebral, or subarachnoid hemorrhage. RESULTS: During the 3-year follow-up period, 339 patients with dementia (12.06%) and 691 patients without dementia (4.92%) developed stroke. The adjusted HRs of developing stroke among newly diagnosed dementia patients were 2.33-times (range, 2.05-2.66), and the incidence of hemorrhagic stroke was higher than that of other stroke types. Patients who had Alzheimer's disease were at the highest risk of hemorrhagic stroke. CONCLUSION: Individuals with dementia, especially Alzheimer's disease, are at greater risk of developing stroke, especially in intracerebral and subarachnoid hemorrhage than patients without dementia. Early mental screening programs and health education should be initiated for dementia patients.

Cordyceps sinensis protects against renal ischemia/reperfusion injury in rats.

Cordyceps sinensis (CS) is an entomogenous fungus used as a tonic food and Chinese medicine to replenish health. This study investigated the protective effects of CS in rats post-renal ischemia-reperfusion (I/R) sequence by analyzing the influence on stromal cell-derived factor-1α (SDF-1α and chemokine (C-X-C motif) receptor 4 (CXCR4) expressions and senescence during recovery. Chemokine SDF-1 [now called chemokine C-X-C motif ligand 12 (CXCL12)] and its receptor CXCR4 are crucial in kidney repair after ischemic acute renal failure. CS treatment significantly alleviated I/R-induced renal damage assessed by creatinine levels (p < 0.05) and abated renal tubular damages assessed by periodic acid-Schiff with diastase (PASD) staining. CS induced early SDF-1α expression and increased CXCR4 expression 1-6 h post-reperfusion. Histology studies have revealed that CS induced SDF-1α in squamous cells of Bowman's capsule, mesangial cells, distal convoluted tubules (DCT), and proximal convoluted tubules (PCT). CS also improved renal repair in I/R-induced injury by increasing Ki-67 staining. I/R induced renal senescence after 3 and 6 h of reperfusion. However, CS alleviated I/R-induced senescence at early stage (1 and 3 h). We conclude that CS protects against I/R injury via the SDF-1/CXCR4-signaling axis and alleviates senescence.

Salvia miltiorrhiza causes tonic contraction in rat ileum through Ca²âº-calmodulin pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Danshen, root of Salvia miltiorrhiza (SM), has been traditionally used in Chinese medicine for the treatment of heart, abdomen, gurgling in the intestines, and relieving fullness. However, the effects of SM on intestine have rarely been done to date. AIM OF THE STUDY: To investigate the contraction effect of SM on isolated rat ileum and its mechanisms involved. MATERIALS AND METHODS: The isometric contractions of ileum segments were investigated in organ baths for spontaneous activity and response to ethanolic extracts of SM. To determine the contraction mechanism caused by SM extracts, atropine (a muscarinic receptor antagonist), tetrodotoxin (TTX, a sodium channel blocker), nifedipine (a calcium channel blocker), Ca(2+) free Krebs solution with EGTA, or trifluoperazine (TFP, a calmodulin blocker) was administered and its response to cumulative dosages of SM extracts were examined. The effect of SM extracts on Ca(2+) signaling in the intestinal epithelial cell-6 (IEC-6) was examined using fura-2 as a Ca(2+) indicator. RESULTS: SM extracts caused dose-dependent tonic contraction on rat ileum in ex vivo organ bath studies. The contraction induced by SM extracts was not inhibited by atropine, TTX, nifedipine, or in Ca(2+) free solution. However, the ileal contractions induced by SM extracts were significantly inhibited by TFP in a dose-dependent manner. In IEC-6 cells, the SM extracts induced extracellular Ca(2+) entry and massive intracellular Ca(2+) release in Ca(2+)-contained medium, and induced intracellular Ca(2+) release in Ca(2+)-free medium. CONCLUSION: These results demonstrate that SM extracts cause ileal contraction through the Ca(2+)-calmodulin pathway.

Preparation, characterization and cytotoxicity evaluation of tanshinone IIA nanoemulsions.

Tanshinone IIA (TA) is a major active component of Danshen (Salvia miltiorrhiza bunge), a well-known traditional Chinese medicine. In this paper, we describe an optimal method for preparing TA nanoemulsions (TA-NEs) to solve the problems of TA's poor solubility in water and insufficient dissolution rate. Optimization of the method for preparing nanoemulsions of lipid soluble TA by emulsification/high pressure homogenization was carried out with a 2(3) factorial design, using Tween 80, lecithin and water content as independent variables. The particle size, entrapment efficiency and polydispersity index of eight formulations were then evaluated. Two optimal formulations, TA-NE-F2 and TA-NE-F4, were developed and both exhibited markedly enhanced in vitro release ability, as compared to TA. However, only TA-NE-F4 remained stable for over 3 months. TA-NE-F4 particles were spherical and intact, with a mean particle size of 95.6 nm and a high entrapment efficiency of 99.3%, TA-NE-F4 showed a fast dissolution rate of 80% in 10 min and 100% in 20 min. The cytotoxicity of TA-NE-F4 against T24 human bladder cancer cells was 103.4-fold greater than TA alone in both a time- and a dose-dependent manner. Overall, we describe a feasible method for preparing TA-NEs that exhibit potent cytotoxicity.

Solanum incanum extract (SR-T100) induces human cutaneous squamous cell carcinoma apoptosis through modulating tumor necrosis factor receptor signaling pathway.

BACKGROUND: The Solanum species herbs have been used to treat cancer for centuries; however, the underlying mechanisms and effectiveness in vivo remain unclear. OBJECTIVES: SR-T100, extracted from the Solanum incanum, contains solamargine alkaloid as the main active ingredient. Here, we investigated the apoptosis-inducing effects of SR-T100 for targeting squamous cell carcinoma (SCC) in vitro and in vivo. METHODS: We elucidated the mechanism by which SR-T100 induces apoptosis of human SCCs (A431, SCC4, SCC9, and SCC25) cells. The efficacy and safety issues were addressed regarding topical treatment of SR-T100 on UVB-induced cutaneous SCC of hairless mice and actinic keratoses (AKs) of human. RESULTS: SR-T100 induces apoptosis in human SCCs cell lines by up-regulating the expressions of tumor necrosis factor receptors (TNFRs) and Fas, and downstream adaptors FADD/TRADD of the TNF-α and Fas ligand signaling cascades. SR-T100 also triggered the mitochondrial apoptotic pathway, as up-regulated cytochrome c and Bax, down-regulated Bcl-X(L). Animal experiments showed that all papillomas (35/35) and 27 of 30 UVB-induced microinvasive SCCs in hairless mice disappeared within 10 weeks after once-daily application of topical SR-T100. Furthermore, 13 patients, who suffered with 14 AKs, were treated with once-daily topical SR-T100 gel and 10 AKs cured after 16 weeks, showing negligible discomforts. CONCLUSION: Our studies indicate that SR-T100 induces apoptosis of SCC cells via death receptors and the mitochondrial death pathway. The high efficacy of SR-T100 in our preclinical trial suggests that SR-T100 is a highly promising herb for AKs and related disorders.

Substance P acts via the neurokinin receptor 1 to elicit bronchoconstriction, oxidative stress, and upregulated ICAM-1 expression after oil smoke exposure.

This study aimed to 1) assess whether substance P (SP) acts via neurokinin (NK)-1 and NK-2 receptors to stimulate neurogenic inflammation (indicated by formation of ICAM-1 expression and oxidative stress) following oil smoke exposure (OSE) in rats; and 2) determine if pretreatment with antioxidants ameliorates the deleterious effects of OSE. Rats were pretreated with NK-1 receptor antagonist CP-96345, NK-2 receptor antagonist SR-48968, vitamin C, or catechins. OSE was for 30-120 min. Rats were killed 0-8 h later. Total lung resistance (RL), airway smooth muscle activity (ASMA), lung ICAM-1 expression, neurogenic plasma extravasation (via India ink and Evans blue dye), bronchoalveolar lavage fluid SP concentrations, and reactive oxygen species formation [via lucigenin- and luminal-amplified chemiluminescence (CL)] were assessed. Lung histology was performed. SP concentrations increased significantly in nonpretreated rats following OSE in a dose-dependent manner. RL and total ASMA increased over time after OSE. Vitamin C and catechin pretreatments were associated with significantly reduced lucigenin CL 2 and 4 h after OSE. Pretreatment with catechins significantly reduced luminal CL counts 4 and 8 h after OSE. Evans blue levels were significantly reduced following 60 and 120 min of OSE in catechin- and CP-96345-pretreated rats. ICAM-1 protein expression was significantly decreased in all pretreatment groups after OSE. Thickening of the alveolar capillary membrane, focal hemorrhaging, interstitial pneumonitis, and peribronchiolar inflammation were apparent in OSE lungs. These findings suggest that SP acts via the NK-1 receptor to provoke neurogenic inflammation, oxidative stress, and ICAM-1 expression after OSE in rats.