Role of catecholamines in the inhibitory effect of immobilization stress on testosterone secretion in rats.

ABSTRACT The response of prolactin to chronic stress in intact, adrenalectomized and adrenomedullectomized male rats was studied. Immobilization stress in intact animals induced a significant increase in plasma concentrations of prolactin after 20 and 45 min and a significant decrease when the rats were submitted to chronic restraint (6 h daily for 4 days). Five weeks after adrenomedullectomy, plasma prolactin and corticosterone responses to chronic stress were not modified. In contrast, the inhibitory effect of chronic stress on prolactin secretion was totally suppressed by adrenalectomy. When treated with dexamethasone during the 4 days of restraint, adrenalectomized stressed rats showed similar plasma concentrations of prolactin to the intact stressed rats. These data indicate that the adrenal cortex is able to play an inhibitory role on prolactin secretion during stress only through a prolonged release of glucocorticoids. Journal of Endocrinology (1989) 120, 269–273

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Influence of nandrolondecanoate on the pituitary-gonadal axis in males

Acta Endocrinologica ◽

10.1530/acta.0.1010108 ◽

1982 ◽

Vol 101 (1) ◽

pp. 108-112 ◽

Cited By ~ 20

Author(s):

J. W. J. Bijlsma ◽

S. A. Duursma ◽

J. H. H. Thijssen ◽

O. Huber

Keyword(s):

Rheumatoid Arthritis ◽

Pilot Study ◽

Beneficial Effect ◽

Sex Steroids ◽

Anabolic Steroids ◽

Serum Levels ◽

Inhibitory Effect ◽

Testosterone Secretion ◽

Lh Secretion

Abstract. Different anabolic steroids can exercise different effects on the pituitary-gonadal axis in males. During a pilot study regarding the possible beneficial effect of the anabolic steroid nandrolondecanoate (ND) on bone metabolism in patients with rheumatoid arthritis additional endocrinological parameters were studied. A significant decrease was found in the serum levels of testosterone, androstenedione and FSH and the ratio of testosterone/oestradiol. There was a significant increase in the serum levels of oestrone. The levels of oestradiol, SHBG, LH and cortisol remained unchanged. An inhibitory effect of ND on testicular testosterone secretion is assumed. The decrease in androstenedione levels is explained by the diminished testosterone secretion. The rise in oestrone levels is explained by peripheral aromatizing of ND to oestrogens. The presented findings are in accordance with the hypothesis that sex steroids can act directly on the pituitary resulting in selective FSH and LH secretion. The possible role of the ratio testosterone/oestradiol in controlling gonadotrophin output is discussed.

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The Inhibitory Effect of Intracerebroventricularly Injected Interleukin 1β on Testosterone Secretion in the Rat: Role of Steroidogenic Acute Regulatory Protein1

Biology of Reproduction ◽

10.1095/biolreprod60.2.527 ◽

1999 ◽

Vol 60 (2) ◽

pp. 527-533 ◽

Cited By ~ 33

Author(s):

Kathleen M. Ogilvie ◽

Karen Held Hales ◽

Maretha E. Roberts ◽

Dale Buchanan Hales ◽

Catherine Rivier

Keyword(s):

Inhibitory Effect ◽

Interleukin 1Β ◽

Testosterone Secretion ◽

Steroidogenic Acute Regulatory

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Effect of Dipyridamole on Spontaneous Platelet Aggregation in Whole Blood Decreases with the Time After Venepuncture: Evidence for the Role of ADP

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645978 ◽

1987 ◽

Vol 58 (02) ◽

pp. 744-748 ◽

Cited By ~ 11

Author(s):

A R Saniabadi ◽

G D O Lowe ◽

J C Barbenel ◽

C D Forbes

Keyword(s):

Platelet Aggregation ◽

Correlation Coefficient ◽

Whole Blood ◽

Blood Platelet ◽

Inhibitory Effect ◽

Time Interval ◽

Adp Receptor ◽

Spontaneous Platelet Aggregation

SummarySpontaneous platelet aggregation (SPA) was studied in human whole blood at 3, 5, 10, 20, 30, 40 and 60 minutes after venepuncture. Using a whole blood platelet counter, SPA was quantified by measuring the fall in single platelet count upon rollermixing aliquots of citrated blood at 37° C. The extent of SPA increased with the time after venepuncture, with a correlation coefficient of 0.819. The inhibitory effect of dipyridamole (Dipy) on SPA was studied: (a) 10 μM at each time interval; (b) 0.5-100 μM at 3 and 30 minutes and (c) 15 μM in combination with 100 μM adenosine, 8 μM 2-chloroadenosine (2ClAd, an ADP receptor blocker) and 50 μM aspirin. There was a rapid decrease in the inhibitory effect of Dipy with the time after venepuncture; the correlation coefficient was -0.533. At all the concentrations studied, Dipy was more effective at 3 minutes than at 30 minutes after venepuncture. A combination of Dipy with adenosine, 2ClAd or aspirin was a more effective inhibitor of SPA than either drug alone. However, when 15 μM Dipy and 10 μM Ad were added together, the inhibitory effect of Dipy was not increased significantly, suggesting that Dipy inhibits platelet aggregation independent of Ad. The increase in SPA with the time after venepuncture was abolished when blood was taken directly into the anticoagulant containing 5 μM 2ClAd. It is suggested that ADP released from the red blood cells is responsible for the increased platelet aggregability with the time after venepuncture and makes a serious contribution to the artifacts of in vitro platelet function studies.

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Effect of human galanin on the response of circulating catecholamines to hypoglycemia in man

Acta Endocrinologica ◽

10.1530/eje.0.1330723 ◽

1995 ◽

Vol 133 (6) ◽

pp. 723-728 ◽

Cited By ~ 4

Author(s):

Ettore C degli Uberti ◽

Maria R Ambrosio ◽

Marta Bondanelli ◽

Giorgio Transforini ◽

Alberto Valentini ◽

...

Keyword(s):

Heart Rate ◽

Healthy Subjects ◽

Sympathetic Nerve Activity ◽

Heart Rate Response ◽

Statistical Significance ◽

Inhibitory Effect ◽

Amino Acid Residues ◽

Nerve Activity ◽

Receptor Stimulation

degli Uberti EC, Ambrosio MR, Bondanelli M, Trasforini G, Valentini A, Rossi R, Margutti A, Campo M. Effect of human galanin on the response of circulating catecholamines to hypoglycemia in man. Eur J Endocrinol 1995;133:723–8. ISSN 0804–4643 Human galanin (hGAL) is a neuropeptide with 30 amino acid residues that has been found in the peripheral and central nervous system, where it often co-exists with catecholamines. In order to clarify the possible role of hGAL in the regulation of sympathoadrenomedullary function, the effect of a 60 min infusion of hGAL (80 pmol·kg−1 · min−1) on plasma epinephrine and norepinephrine responses to insulin-induced hypoglycemia in nine healthy subjects was investigated. Human GAL administration significantly reduced both the release of basal norepinephrine and the response to insulin-induced hypoglycemia, whereas it attenuated the epinephrine response by 26%, with the hGAL-induced decrease in epinephrine release failing to achieve statistical significance. Human GAL significantly increased the heart rate in resting conditions and clearly exaggerated the heart rate response to insulin-induced hypoglycemia, whereas it had no effect on the blood pressure. We conclude that GAL receptor stimulation exerts an inhibitory effect on basal and insulin-induced hypoglycemia-stimulated release of norepinephrine. These findings provide further evidence that GAL may modulate sympathetic nerve activity in man but that it does not play an important role in the regulation of adrenal medullary function. Ettore C degli Uberti, Chair of Endocrinology, University of Ferrara, Via Savonarola 9, I-44100 Ferrara, Italy

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Biological role of AKT, and regulation of AKT signaling pathway by thymoquinone: perspectives in cancer therapeutics

Mini-Reviews in Medicinal Chemistry ◽

10.2174/1389557520666201005143818 ◽

2020 ◽

Vol 20 ◽

Author(s):

Md. Junaid ◽

Yeasmin Akter ◽

Syeda Samira Afrose ◽

Mousumi Tania ◽

Md. Asaduzzaman Khan

Keyword(s):

Clinical Trials ◽

Signaling Pathways ◽

Signaling Pathway ◽

Inhibitory Effect ◽

Akt Signaling ◽

Review Article ◽

Therapeutic Drug ◽

Akt Signaling Pathway ◽

Anti Cancer

Background: AKT/PKB is an important enzyme with numerous biological functions, and its overexpression is related to the carcinogenesis. AKT stimulates different signaling pathways that are downstream of activated tyrosine kinases and phosphatidylinositol 3-kinase, hence functions as an important target for anti-cancer drugs. Objective: In this review article, we have interpreted the role of AKT signaling pathways in cancer and natural inhibitory effect of Thymoquinone (TQ) in AKT and its possible mechanism. Method: We have collected the updated information and data on AKT, their role in cancer and inhibitory effect of TQ in AKT signaling pathway from google scholar, PubMed, Web of Science, Elsevier, Scopus and many more. Results: There are many drugs already developed, which can target AKT, but very few among them have passed clinical trials. TQ is a natural compound, mainly found in black cumin, which has been found to have potential anti-cancer activities. TQ targets numerous signaling pathways, including AKT, in different cancers. In fact, many studies revealed that AKT is one of the major targets of TQ. The preclinical success of TQ suggests its clinical studies on cancer. Conclusion: This review article summarizes the role of AKT in carcinogenesis, its potent inhibitors in clinical trials, and how TQ acts as an inhibitor of AKT and TQ’s future as a cancer therapeutic drug.

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The Immunomodulatory Role of G2013 (α-L-Guluronic Acid) on the Expression of TLR2 and TLR4 in HT29 cell line

Current Drug Discovery Technologies ◽

10.2174/1570163815666180226093711 ◽

2019 ◽

Vol 16 (1) ◽

pp. 91-95 ◽

Cited By ~ 4

Author(s):

Hamid Farhang ◽

Laleh Sharifi ◽

Mohammad Mehdi Soltan Dallal ◽

Mona Moshiri ◽

Zahra Norouzbabaie ◽

...

Keyword(s):

Inflammatory Responses ◽

Inflammatory Diseases ◽

Rna Extraction ◽

Cell Plate ◽

Inhibitory Effect ◽

Control Group ◽

Ht29 Cells ◽

Guluronic Acid ◽

Tlr4 Mrna

Background: The non-steroidal anti-inflammatory drugs (NSAIDs) play crucial role in the controlling of inflammatory diseases. Due to the vast side effects of NSAIDs, its use is limited. G2013 or &#945;-L-Guluronic Acid is a new NSAID with immunomodulatory features. Objectives: Considering the leading role of TLRs in inflammatory responses, in this study, we aimed to evaluate G2013 cytotoxicity and its effect on the expression of TLR2 and TLR4 molecules. Methods: HEK293-TLR2 and HEK293-TLR4 cells were cultured and seeded on 96-well cell plate, and MTT assay was performed for detecting the viability of the cells after treatment with different concentrations of G2013. HT29 cells were grown and treated with low and high doses of G2013. After total RNA extraction and cDNA synthesis, quantitative real-time PCR were performed to assess the TLR2 and TLR4 mRNA synthesis. Results: We found that concentrations of ≤125 &#181;g/ml of G2013 had no apparent cytotoxicity effect on the HEK293-TLR2 and -TLR4 cells. Our results indicated that after G2013 treatment (5 &#181;g/ml) in HT29 cells, TLR2 and TLR4 mRNA expression decreased significantly compared with the untreated control group (p=0.02 and p=0.001 respectively). Conclusion: The results of this study revealed that G2013 can down regulate the TLR2 and TLR4 gene expression and exerts its inhibitory effect. Our findings are parallel to our previous finding which showed G2013 ability to down regulate the signaling pathway of TLRs. However, further studies are needed to identify the molecular mechanism of G2013.<p>

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Albizia chinensis bark extract ameliorates the genotoxic effect of cyclophosphamide

Bulletin of the National Research Centre ◽

10.1186/s42269-020-00422-9 ◽

2020 ◽

Vol 44 (1) ◽

Author(s):

Marian Nabil ◽

Entesar E. Hassan ◽

Neven S. Ghaly ◽

Fawzia A. Aly ◽

Farouk R. Melek ◽

...

Keyword(s):

Folk Medicine ◽

Inhibitory Effect ◽

Protective Role ◽

Bark Extract ◽

Repeated Treatment ◽

Mouse Bone Marrow ◽

Sperm Abnormalities ◽

Wide Range ◽

Different Doses

Abstract Background The genus Albizia (Leguminoseae) is used in folk medicine for the treatment of a wide range of ailments. Recently, saponins from plant origin have attracted much attention. Saponins are recorded to have a broad range of biological and pharmacological activities. This study was performed to evaluate the protective role of Albizia chinensis bark methanolic extract (MEAC) against the genotoxicity induced by cyclophosphamide (CP) using different mutagenic parameters. Results The results showed that MEAC induced an inhibitory effect against chromosomal aberrations of CP in mouse bone marrow and spermatocytes. Such effect was found to be significant (p < 0.01) with a dose of 100 mg/kg treated once for 24 h and also after repeated treatment at a dose of 25 mg/kg for 7 days. In sperm abnormalities, the protective effect of Albizia extract showed a dose-related relationship. Different doses of MEAC (25, 50, and 100 mg/kg) significantly (p < 0.01) ameliorated sperm abnormalities induced by CP dose-dependently. The percentage of sperm abnormalities was decreased to 5.14 ± 0.72 in the group of animals treated with CP plus MEAC (100 mg/kg) indicating an inhibitory effect of about 50%. Conclusion MEAC at the doses examined was non-genotoxic compared to control (negative) and exhibited a protective role against CP genotoxicity.

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POSSIBLE ROLE OF 5α-ANDROSTANE-3α,17β-DIOL IN THE CONTROL OF FOLLICLE-STIMULATING HORMONE SECRETION IN THE IMMATURE FEMALE RAT

Journal of Endocrinology ◽

10.1677/joe.0.0920037 ◽

1982 ◽

Vol 92 (1) ◽

pp. 37-42 ◽

Cited By ~ 10

Author(s):

H. M. A. MEIJS-ROELOFS ◽

P. KRAMER ◽

L. GRIBLING-HEGGE

Keyword(s):

Inhibitory Action ◽

Combined Treatment ◽

Hormone Secretion ◽

Inhibitory Effect ◽

Ovariectomized Rats ◽

Female Rat ◽

Immature Rat ◽

Rat Strain ◽

Intact Rats

A possible role of 5α-androstane-3α,17β-diol (3α-androstanediol) in the control of FSH secretion was studied at various ages in ovariectomized rats. In the rat strain used, vaginal opening, coincident with first ovulation, generally occurs between 37 and 42 days of age. If 3α-androstanediol alone was given as an ovarian substitute, an inhibitory effect on FSH release was evident with all three doses tested (50, 100, 300 μg/100 g body wt) between 13 and 30 days of age; at 33–35 days of age only the 300 μg dose caused some inhibition of FSH release. Results were more complex if 3α-androstanediol was given in combined treatment with oestradiol and progesterone. Given with progesterone, 3α-androstanediol showed a synergistic inhibitory action on FSH release between 20 and 30 days of age. However, when 3α-androstanediol was combined with oestradiol a clear decrease in effect, as compared to the effect of oestradiol alone, was found between 20 and 30 days of age. Also the effect of combined oestradiol and progesterone treatment was greater than the effect of combined treatment with oestradiol, progesterone and 3α-androstanediol. At all ages after day 20 none of the steroid combinations tested was capable of maintaining FSH levels in ovariectomized rats similar to those in intact rats. It is concluded that 3α-androstanediol might play a role in the control of FSH secretion in the immature rat, but after day 20 the potentially inhibitory action of 3α-androstanediol on FSH secretion is limited in the presence of oestradiol.

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F4/80+ Kupffer Cell-Derived Oncostatin M Sustains the Progression Phase of Liver Regeneration through Inhibition of TGF-β2 Pathway

Molecules ◽

10.3390/molecules26082231 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2231

Author(s):

Qingjun Lu ◽

Hao Shen ◽

Han Yu ◽

Jing Fu ◽

Hui Dong ◽

...

Keyword(s):

Liver Regeneration ◽

Serum Levels ◽

Inhibitory Effect ◽

Regenerative Process ◽

Oncostatin M ◽

Hepatocyte Proliferation ◽

Initiation Phase ◽

Distinct Role

The role of Kupffer cells (KCs) in liver regeneration is complicated and controversial. To investigate the distinct role of F4/80+ KCs at the different stages of the regeneration process, two-thirds partial hepatectomy (PHx) was performed in mice to induce physiological liver regeneration. In pre- or post-PHx, the clearance of KCs by intraperitoneal injection of the anti-F4/80 antibody (α-F4/80) was performed to study the distinct role of F4/80+ KCs during the regenerative process. In RNA sequencing of isolated F4/80+ KCs, the initiation phase was compared with the progression phase. Immunohistochemistry and immunofluorescence staining of Ki67, HNF-4α, CD-31, and F4/80 and Western blot of the TGF-β2 pathway were performed. Depletion of F4/80+ KCs in pre-PHx delayed the peak of hepatocyte proliferation from 48 h to 120 h, whereas depletion in post-PHx unexpectedly led to persistent inhibition of hepatocyte proliferation, indicating the distinct role of F4/80+ KCs in the initiation and progression phases of liver regeneration. F4/80+ KC depletion in post-PHx could significantly increase TGF-β2 serum levels, while TGF-βRI partially rescued the impaired proliferation of hepatocytes. Additionally, F4/80+ KC depletion in post-PHx significantly lowered the expression of oncostatin M (OSM), a key downstream mediator of interleukin-6, which is required for hepatocyte proliferation during liver regeneration. In vivo, recombinant OSM (r-OSM) treatment alleviated the inhibitory effect of α-F4/80 on the regenerative progression. Collectively, F4/80+ KCs release OSM to inhibit TGF-β2 activation, sustaining hepatocyte proliferation by releasing a proliferative brake.

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