Chronic Stimulation of the Autophagy-inducing Ingredient of Areca Nut Promotes Tumor Growth In Vivo Through Up-regulation of Tumoral Autophagy

Abstract Like VEGF, morphine stimulates MAPK/ERK and Akt, leading to the promotion of angiogenesis via NO dependent signaling (Cancer Res62: 4491, 2002). Morphine acts via pertussis toxin (PT)-dependent G-protein coupled receptors (GPCRS), while VEGF acts via receptor tyrosine kinases (RTKs). We showed that PT-dependent GPCRs transactivate VEGF receptor-2/Flk1 via small GTPase RhoA (JBC277: 4679, 2002; JBC278:20738, 2003). Therefore, we hypothesized that morphine via the mu opioid receptor (MOR) transactivates Flk1 and promotes a pro-angiogenic microenvironment. Morphine-induced proliferation of human umbilical vein endothelial cells (HUVEC) was completely abrogated by Y-27632 (100 μM), a highly selective and potent inhibitor of Rho-associated protein kinases, suggesting the activation of Rho signaling by morphine. Addition of 1 μM morphine potentiated VEGF-induced (10 ng/ml) proliferation of HUVEC by 25%. We observed a 30% increase in intracellular calcium release after VEGF stimulation of HUVEC pre-incubated with morphine as compared to HUVEC pre-incubated with PBS, detected by a change in the fluorescence ratio of the Fura-2 AM dye. These findings show that morphine, via MOR and Rho signaling, transactivates Flk1 leading to the stimulation of calcium signaling and endothelial cell proliferation. To functionally corroborate our hypothesis, we used MOR knockout (MOR-KO) mice and injected them with MOR-replete T241 fibrosarcoma cells. T241 fibrosarcoma tumor growth in vivo showed appearance of palpable and measurable tumors 2 days earlier in wild type (wt) as compared to MOR-KO mice. Tumor growth and angiogenesis were decreased by 20–35% in MOR-KO mice as compared to wt littermates during 3 weeks of tumor growth. None of the MOR-KO showed signs of lung metastasis versus 40% wt mice with metastasis. Morphine (1.42 for the first 2 wks and 2.14 mg/Kg/day later, respectively) stimulated 20–35% tumor growth in wt, but not in MOR-KO mice. Western immunoblotting showed a 10-fold increase in the expression of phospho-Flk1 in morphine treated wt tumors as compared to PBS-treated wt mice. Morphine did not stimulate phospho-Flk1 expression in MOR-KO mice. Western analysis of immunoprecipitates obtained with α-MOR antibody showed the expression of Flk1 and phospho-Flk1 in wt, but were not expressed in MOR-KO tumors. Thus, MOR stimulates the transactivation of Flk1 in wt mice but not in MOR-KO. These in vitro and in vivo data using MOR-KO mice and the MOR agonist, morphine, show that MOR stimulates endothelial proliferation, angiogenesis and promotes tumor growth and metastasis directly as well as by transactivating Flk1 phosphorylation. We speculate that MOR is a critical component of the ‘angiogenic switch’, which regulates the pro-angiogenic and growth promoting tumor microenvironment. Thus, MOR provides a novel target for developing anti-angiogenic therapies.

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Production of corticosterone and testosterone in scorbutic mutant rats: difference of in vivo production between adrenal gland and testis

Acta Endocrinologica ◽

10.1530/acta.0.1240425 ◽

1991 ◽

Vol 124 (4) ◽

pp. 425-433 ◽

Cited By ~ 5

Author(s):

Haruki Fukuda ◽

Yasuhiro Ito ◽

Ryouji Hirota ◽

Motomu Tsuji ◽

Hiroshi Mori

Keyword(s):

Ascorbic Acid ◽

Adrenal Gland ◽

Steroid Hormones ◽

Mutant Strain ◽

Seminal Vesicles ◽

Plasma Acth ◽

Chronic Stimulation ◽

Testosterone Levels ◽

Stimulation Of

Abstract. Effects of deficiency in ascorbic acid on in vivo production of corticosterone and testosterone were examined using a mutant strain of rats unable to synthesize ascorbic acid. The adrenal weight of scorbutic rats was larger, and corticosterone levels in plasma and adrenal tissues were higher than those of ascorbic acid-supplied (ascorbutic) rats. Acute and chronic stimulation with ACTH increased corticosterone levels in both ascorbutic and scorbutic rats. In contrast, weights of seminal vesicles and ventral prostates in unstimulated scorbutic rats were smaller, and testosterone levels in plasma and testicular tissues were lower than those in ascorbutic rats. Acute stimulation with hCG increased testosterone levels only slightly in plasma and not in testicular tissues of scorbutic rats, when testosterone levels in ascorbutic rats reached a maximum. Chronic stimulation with hCG increased testosterone levels remarkably in both ascorbutic and scorbutic rats. These findings seem to indicate that ascorbic acid is not essential for the synthesis of steroid hormones. The scurvy seems to increase plasma ACTH levels secondary to the stress, resulting in the stimulation of the adrenals. In contrast, a prolonged deficiency in ascorbic acid appears to decrease plasma gonadotropin levels, and may reduce the sensitivity of testes to gonadotropins.

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Reversal of right ventricular failure by chronic α1A-subtype adrenergic agonist therapy

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00507.2018 ◽

2019 ◽

Vol 316 (1) ◽

pp. H224-H232 ◽

Cited By ~ 3

Author(s):

Patrick M. Cowley ◽

Guanying Wang ◽

Philip M. Swigart ◽

Anaha Raghunathan ◽

Nikitha Reddy ◽

...

Keyword(s):

Pulmonary Artery ◽

Right Ventricular ◽

Therapeutic Target ◽

Adrenergic Receptors ◽

Chronic Stimulation ◽

Pulmonary Artery Constriction ◽

Rv Function ◽

Fractional Shortening ◽

Stimulation Of

Right ventricular (RV) failure (RVF) is a serious disease with no effective treatment available. We recently reported a disease prevention study showing that chronic stimulation of α1A-adrenergic receptors (α1A-ARs), started at the time of RV injury, prevented the development of RVF. The present study used a clinically relevant disease reversal design to test if chronic α1A-AR stimulation, started after RVF was established, could reverse RVF. RVF was induced surgically by pulmonary artery constriction in mice. Two weeks after pulmonary artery constriction, in vivo RV fractional shortening as assessed by MRI was reduced by half relative to sham-operated controls (25 ± 2%, n = 27, vs. 52 ± 2%, n = 13, P < 10−11). Subsequent chronic treatment with the α1A-AR agonist A61603 for a further 2 wk resulted in a substantial recovery of RV fractional shortening (to 41 ± 2%, n = 17, P < 10−7 by a paired t-test) along with recovery of voluntary exercise capacity. Mechanistically, chronic A61603 treatment resulted in increased activation of the prosurvival kinase ERK, increased abundance of the antiapoptosis factor Bcl-2, and decreased myocyte necrosis evidenced by a decreased serum level of cardiac troponin. Moreover, A61603 treatment caused increased abundance of the antioxidant glutathione peroxidase-1, decreased level of reactive oxygen species, and decreased oxidative modification (carbonylation) of myofilament proteins. Consistent with these effects, A61603 treatment resulted in increased force development by cardiac myofilaments, which might have contributed to increased RV function. These findings suggest that the α1A-AR is a therapeutic target to reverse established RVF. NEW & NOTEWORTHY Currently, there are no effective therapies for right ventricular (RV) failure (RVF). This project evaluated a novel therapy for RVF. In a mouse model of RVF, chronic stimulation of α1A-adrenergic receptors with the agonist A61603 resulted in recovery of in vivo RV function, improved exercise capacity, reduced oxidative stress-related carbonylation of contractile proteins, and increased myofilament force generation. These results suggest that the α1A-adrenergic receptor is a therapeutic target to treat RVF.

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Changes in cyclic AMP level of rat thyroid by acute and chronic stimulation of thyrotropin in vivo.

Endocrinologia Japonica ◽

10.1507/endocrj1954.23.157 ◽

1976 ◽

Vol 23 (2) ◽

pp. 157-163 ◽

Cited By ~ 2

Author(s):

YASUKO NAKAMURA ◽

MITSUO SUZUKI ◽

ISAO KOBAYASHI ◽

YONOSUKE SHIMOMURA ◽

TADAO KAKEGAWA

Keyword(s):

Cyclic Amp ◽

Chronic Stimulation ◽

Rat Thyroid ◽

Stimulation Of

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Selective stimulation of mast cells with a TLR2 agonist inhibits tumor growth in vivo

The FASEB Journal ◽

10.1096/fasebj.22.1_supplement.1076.14 ◽

2008 ◽

Vol 22 (S1) ◽

Author(s):

Sharon Ann Oldford ◽

Carlos A. Leiva ◽

Brent Johnston ◽

Jean S. Marshall

Keyword(s):

Mast Cells ◽

Tumor Growth ◽

Tlr2 Agonist ◽

Selective Stimulation ◽

Stimulation Of

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Chronic stimulation of the pituitary-adrenal axis in rats by interleukin-1 beta infusion: in vivo and in vitro studies.

Endocrinology ◽

10.1210/endo.130.3.1311230 ◽

1992 ◽

Vol 130 (3) ◽

pp. 1153-1164

Author(s):

C G Sweep ◽

M J van der Meer ◽

A R Hermus ◽

A G Smals ◽

J W van der Meer ◽

...

Keyword(s):

Interleukin 1 ◽

In Vitro Studies ◽

Interleukin 1 Beta ◽

Chronic Stimulation ◽

Adrenal Axis ◽

Pituitary Adrenal Axis ◽

Stimulation Of

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Stimulation of in vivo tumor growth and phorbol ester-induced inflammation by N,N-diethyl-2-[4-(phenylmethyl)phenoxy] ethanamine HCl, a potent ligand for intracellular histamine receptors

Biochemical and Biophysical Research Communications ◽

10.1016/0006-291x(91)91714-n ◽

1991 ◽

Vol 179 (3) ◽

pp. 1297-1304 ◽

Cited By ~ 17

Author(s):

Lorne J. Brandes ◽

Wayne A. Beecroft ◽

Georgina R. Hogg

Keyword(s):

Tumor Growth ◽

Phorbol Ester ◽

Histamine Receptors ◽

Stimulation Of

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Human β3-Adrenoreceptor is Resistant to Agonist-Induced Desensitization in Renal Epithelial Cells

Cellular Physiology and Biochemistry ◽

10.1159/000491916 ◽

2018 ◽

Vol 48 (2) ◽

pp. 847-862 ◽

Cited By ~ 3

Author(s):

Serena Milano ◽

Andrea Gerbino ◽

Giorgia Schena ◽

Monica Carmosino ◽

Maria Svelto ◽

...

Keyword(s):

Epithelial Cells ◽

Chronic Exposure ◽

Collecting Duct ◽

Membrane Localization ◽

Intracellular Camp ◽

Renal Cells ◽

Chronic Stimulation ◽

Stimulation Of

Background/Aims: We recently showed that the β3-adrenoreceptor (β3AR) is expressed in mouse kidney collecting ducts (CD) cells along with the type-2 vasopressin receptor (AVPR2). Interestingly, a single injection of a β3AR selective agonist promotes a potent antidiuretic effect in mice. Before considering the feasibility of chronic β3AR agonism to induce antidiuresis in vivo, we aimed to evaluate in vitro the signaling and desensitization profiles of human β3AR. Methods: Human β3AR desensitization was compared with that of human AVPR2 in cultured renal cells. Video imaging and FRET experiments were performed to dissect β3AR signaling under acute and chronic stimulation. Plasma membrane localization of β3AR, AVPR2 and AQP2 after agonist stimulation was studied by confocal microscopy. Receptors degradation was evaluated by Western blotting. Results: In renal cells acute stimulation with the selective β3AR agonist mirabegron, induced a dose-dependent increase in cAMP. Interestingly, chronic exposure to mirabegron promoted a significant increase of intracellular cAMP up to 12 hours. In addition, a slow and slight agonist-induced internalization and a delayed downregulation of β3AR was observed under chronic stimulation. Furthermore, chronic exposure to mirabegron promoted apical expression of AQP2 also up to 12 hours. Conversely, long-term stimulation of AVPR2 with dDAVP showed short-lasting receptor signaling, rapid internalization and downregulation and apical AQP2 expression for no longer than 3 h. Conclusions: Overall, we conclude that β3AR is less prone than AVPR2 to agonist-induced desensitization in renal collecting duct epithelial cells, showing sustained cAMP production, preserved membrane localization and delayed degradation after 12 hours agonist exposure. These results may be important for the potential use of chronic pharmacological stimulation of β3AR to promote antidiuresis overcoming in vivo renal concentrating defects caused by inactivating mutations of the AVPR2.

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Effect of release-active anti-interferon-gamma antibodies on the course of the tumor process in in vivo experimental models

Nauchno-prakticheskii zhurnal «Patogenez» ◽

10.25557/2310-0435.2018.03.132-134 ◽

2018 ◽

pp. 132-134

Author(s):

Т.Г. Разина ◽

И.А. Эртузун ◽

Е.Н. Амосова ◽

С.Г. Крылова ◽

Е.П. Зуева ◽

...

Keyword(s):

Tumor Growth ◽

Interferon Gamma ◽

Conformational Changes ◽

Hematogenous Metastasis ◽

Walker 256 Carcinosarcoma ◽

Melanoma B16 ◽

Enhanced Production ◽

Walker 256 ◽

Stimulation Of

Интерферон-гамма (ИФН) играет важную роль в иммунных механизмах сдерживания опухолевого процесса, однако в определенных условиях может оказывать проопухолевое действие. Релиз-активные антитела (РА АТ) к ИФН изменяют конформацию молекулы этого цитокина, облегчают его связывание с рецептором и усиливают продукцию эндогенного ИФН. Цель настоящего исследования состояла в изучении влияния РА АТ к ИФН на имеющийся опухолевый процесс на моделях меланомы и карциносаркомы. Методика. Было изучено влияние препарата на течение опухолевого процесса в моделях меланомы В-16 у мышей и карциносаркомы Уокера 256 у крыс. Результаты. У мышей с меланомой В-16, чувствительной к ИФН, тестируемый препарат не стимулировал рост и метастазирование опухоли. В модели карциносаркомы Уокера 256 у крыс РА АТ к ИФН также не влияли на размер опухоли, однако значительно ингибировали гематогенное метастазирование. Заключение. В настоящем исследовании не было выявлено стимулирования опухолевого процесса и метастазирования препаратом РА АТ к ИФН. Interferon-gamma (IFN) plays an important role in antitumor immunity; however, in some circumstances, it may also favor tumor immune evasion. Released-active (RA) anti-IFN antibodies (Abs) are able to induce conformational changes in the IFN molecule and to facilitate its receptor binding, which results in enhanced production of this cytokine. The aim of the present study was to evaluate the effect of RA anti-IFN Abs on the tumor growth in models of melanoma and carcinosarcoma. Methods. The ability of anti-IFN RA Abs to influence the tumor growth was evaluated in the models of melanoma B16 in mice and Walker 256 carcinosarcoma in rats. Results. The exposure of mice with IFN-sensitive melanoma B16 to the tested drug did not result in stimulation of tumor growth and metastasis. RA anti-IFN Abs also did not affect the tumor size in the rat model of Walker 256 carcinosarcoma but significantly inhibited the hematogenous metastasis. Conclusion. In the present study, no stimulation of the tumor process and metastasis by RA anti-IFN Abs were found.

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