LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 34

Search options

  1. Article: Inhibition of Microglial GSK3β Activity Is Common to Different Kinds of Antidepressants: A Proposal for an In Vitro Screen to Detect Novel Antidepressant Principles.

    Kalkman, Hans O

    Biomedicines

    2023  Volume 11, Issue 3

    Abstract: Depression is a major public health concern. Unfortunately, the present antidepressants often are insufficiently effective, whilst the discovery of more effective antidepressants has been extremely sluggish. The objective of this review was to combine ... ...

    Abstract Depression is a major public health concern. Unfortunately, the present antidepressants often are insufficiently effective, whilst the discovery of more effective antidepressants has been extremely sluggish. The objective of this review was to combine the literature on depression with the pharmacology of antidepressant compounds, in order to formulate a conceivable pathophysiological process, allowing proposals how to accelerate the discovery process. Risk factors for depression initiate an infection-like inflammation in the brain that involves activation microglial Toll-like receptors and glycogen synthase kinase-3β (GSK3β). GSK3β activity alters the balance between two competing transcription factors, the pro-inflammatory/pro-oxidative transcription factor NFκB and the neuroprotective, anti-inflammatory and anti-oxidative transcription factor NRF2. The antidepressant activity of tricyclic antidepressants is assumed to involve activation of G
    Language English
    Publishing date 2023-03-07
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2720867-9
    ISSN 2227-9059
    ISSN 2227-9059
    DOI 10.3390/biomedicines11030806
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article: Activation of σ1-Receptors by R-Ketamine May Enhance the Antidepressant Effect of S-Ketamine.

    Kalkman, Hans O

    Biomedicines

    2023  Volume 11, Issue 10

    Abstract: Ketamine is a racemic mixture composed of two enantiomers, S-ketamine and R-ketamine. In preclinical studies, both enantiomers have exhibited antidepressant effects, but these effects are attributed to distinct pharmacological activities. The S- ... ...

    Abstract Ketamine is a racemic mixture composed of two enantiomers, S-ketamine and R-ketamine. In preclinical studies, both enantiomers have exhibited antidepressant effects, but these effects are attributed to distinct pharmacological activities. The S-enantiomer acts as an NMDA-channel blocker and as an opioid μ-receptor agonist, whereas the R-enantiomer binds to σ1-receptors and is believed to act as an agonist. As racemate, ketamine potentially triggers four biochemical pathways involving the AGC-kinases, PKA, Akt (PKB), PKC and RSK that ultimately lead to inhibitory phosphorylation of GSK3β in microglia. In patients with major depressive disorder, S-ketamine administered as a nasal spray has shown clear antidepressant activity. However, when compared to intravenously infused racemic ketamine, the response rate, duration of action and anti-suicidal activity of S-ketamine appear to be less pronounced. The σ1-protein interacts with μ-opioid and TrkB-receptors, whereas in preclinical experiments σ1-agonists reduce μ-receptor desensitization and improve TrkB signal transduction. TrkB activation occurs as a response to NMDA blockade. So, the σ1-activity of R-ketamine may not only enhance two pathways via which S-ketamine produces an antidepressant response, but it furthermore provides an antidepressant activity in its own right. These two factors could explain the apparently superior antidepressant effect observed with racemic ketamine compared to S-ketamine alone.
    Language English
    Publishing date 2023-09-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2720867-9
    ISSN 2227-9059
    ISSN 2227-9059
    DOI 10.3390/biomedicines11102664
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Potential Suicide Prophylactic Activity by the Fish Oil Metabolite, 4-Hydroxyhexenal.

    Kalkman, Hans O

    International journal of molecular sciences

    2022  Volume 23, Issue 13

    Abstract: Low levels of n-3 poly-unsaturated fatty acids (n-3 PUFAs) and high levels of n-6 PUFAs in the blood circulation are associated with an increased risk for suicide. Clinical studies indicate that docosahexaenoic acid (DHA, a n-3 PUFA found in fish-oil) ... ...

    Abstract Low levels of n-3 poly-unsaturated fatty acids (n-3 PUFAs) and high levels of n-6 PUFAs in the blood circulation are associated with an increased risk for suicide. Clinical studies indicate that docosahexaenoic acid (DHA, a n-3 PUFA found in fish-oil) displays protective effects against suicide. It has recently been proposed that the activation of the transcription factor NRF2 might be the pharmacological activity that is common to current anti-suicidal medications. Oxidation products from fish oil, including those from DHA, are electrophiles that reversibly bind to a protein 'KEAP1', which acts as the molecular inhibitor of NRF2 and so indirectly promotes NRF2-transcriptional activity. In the majority of publications, the NRF2-stimulant effect of DHA is ascribed to the metabolite 4-hydroxyhexenal (4HHE). It is suggested to investigate whether 4HHE will display a therapeutically useful anti-suicidal efficacy.
    MeSH term(s) Aldehydes ; Docosahexaenoic Acids/pharmacology ; Eicosapentaenoic Acid ; Fatty Acids, Omega-3/metabolism ; Fish Oils/pharmacology ; Humans ; NF-E2-Related Factor 2/metabolism ; Suicide
    Chemical Substances Aldehydes ; Fatty Acids, Omega-3 ; Fish Oils ; NF-E2-Related Factor 2 ; 4-hydroxyhexenal (109710-37-4) ; Docosahexaenoic Acids (25167-62-8) ; Eicosapentaenoic Acid (AAN7QOV9EA)
    Language English
    Publishing date 2022-06-23
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms23136953
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Inhibition of Microglial GSK3β Activity Is Common to Different Kinds of Antidepressants

    Hans O. Kalkman

    Biomedicines, Vol 11, Iss 806, p

    A Proposal for an In Vitro Screen to Detect Novel Antidepressant Principles

    2023  Volume 806

    Abstract: Depression is a major public health concern. Unfortunately, the present antidepressants often are insufficiently effective, whilst the discovery of more effective antidepressants has been extremely sluggish. The objective of this review was to combine ... ...

    Abstract Depression is a major public health concern. Unfortunately, the present antidepressants often are insufficiently effective, whilst the discovery of more effective antidepressants has been extremely sluggish. The objective of this review was to combine the literature on depression with the pharmacology of antidepressant compounds, in order to formulate a conceivable pathophysiological process, allowing proposals how to accelerate the discovery process. Risk factors for depression initiate an infection-like inflammation in the brain that involves activation microglial Toll-like receptors and glycogen synthase kinase-3β (GSK3β). GSK3β activity alters the balance between two competing transcription factors, the pro-inflammatory/pro-oxidative transcription factor NFκB and the neuroprotective, anti-inflammatory and anti-oxidative transcription factor NRF2. The antidepressant activity of tricyclic antidepressants is assumed to involve activation of G S -coupled microglial receptors, raising intracellular cAMP levels and activation of protein kinase A (PKA). PKA and similar kinases inhibit the enzyme activity of GSK3β. Experimental antidepressant principles, including cannabinoid receptor-2 activation, opioid μ receptor agonists, 5HT2 agonists, valproate, ketamine and electrical stimulation of the Vagus nerve, all activate microglial pathways that result in GSK3β-inhibition. An in vitro screen for NRF2-activation in microglial cells with TLR-activated GSK3β activity, might therefore lead to the detection of totally novel antidepressant principles with, hopefully, an improved therapeutic efficacy.
    Keywords depression risk factor ; microglia ; toll-like receptor ; GSK3β ; NRF2 ; G S -coupled receptor ; Biology (General) ; QH301-705.5
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  5. Article: An Explanation for the Adiponectin Paradox.

    Kalkman, Hans O

    Pharmaceuticals (Basel, Switzerland)

    2021  Volume 14, Issue 12

    Abstract: The adipokine adiponectin improves insulin sensitivity. Functional signal transduction of adiponectin requires at least one of the receptors AdipoR1 or AdipoR2, but additionally the glycosyl phosphatidylinositol-anchored molecule, T-cadherin. ... ...

    Abstract The adipokine adiponectin improves insulin sensitivity. Functional signal transduction of adiponectin requires at least one of the receptors AdipoR1 or AdipoR2, but additionally the glycosyl phosphatidylinositol-anchored molecule, T-cadherin. Overnutrition causes a reduction in adiponectin synthesis and an increase in the circulating levels of the enzyme glycosyl phosphatidylinositol-phospholipase D (GPI-PLD). GPI-PLD promotes the hydrolysis of T-cadherin. The functional consequence of T-cadherin hydrolysis is a reduction in adiponectin sequestration by responsive tissues, an augmentation of adiponectin levels in circulation and a (further) reduction in signal transduction. This process creates the paradoxical situation that adiponectin levels are augmented, whereas the adiponectin signal transduction and insulin sensitivity remain strongly impaired. Although both hypoadiponectinemia and hyperadiponectinemia reflect a situation of insulin resistance, the treatments are likely to be different.
    Language English
    Publishing date 2021-12-04
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2193542-7
    ISSN 1424-8247
    ISSN 1424-8247
    DOI 10.3390/ph14121266
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article: The Association Between Vascular Inflammation and Depressive Disorder. Causality, Biomarkers and Targeted Treatment.

    Kalkman, Hans O

    Pharmaceuticals (Basel, Switzerland)

    2020  Volume 13, Issue 5

    Abstract: Diabetes, obesity, atherosclerosis, and myocardial infarction are frequently co-morbid with major depressive disorder. In the current review, it is argued that vascular inflammation is a factor that is common to all disorders and that an endothelial ... ...

    Abstract Diabetes, obesity, atherosclerosis, and myocardial infarction are frequently co-morbid with major depressive disorder. In the current review, it is argued that vascular inflammation is a factor that is common to all disorders and that an endothelial dysfunction of the blood-brain barrier could be involved in the induction of depression symptoms. Biomarkers for vascular inflammation include a high plasma level of C-reactive protein, soluble cell-adhesion molecules, von Willebrand factor, aldosterone, and proinflammatory cytokines like interleukin-6 or tumor necrosis factor α. A further possible biomarker is flow-mediated dilation of the brachial artery. Treatment of vascular inflammation is expected to prevent or to reduce symptoms of depression. Several tentative treatments for this form of depression can be envisioned: eicosapentaenoic acid (EPA), valproate,
    Language English
    Publishing date 2020-05-12
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2193542-7
    ISSN 1424-8247
    ISSN 1424-8247
    DOI 10.3390/ph13050092
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article ; Online: Potential Suicide Prophylactic Activity by the Fish Oil Metabolite, 4-Hydroxyhexenal

    Hans O. Kalkman

    International Journal of Molecular Sciences, Vol 23, Iss 6953, p

    2022  Volume 6953

    Abstract: Low levels of n-3 poly-unsaturated fatty acids (n-3 PUFAs) and high levels of n-6 PUFAs in the blood circulation are associated with an increased risk for suicide. Clinical studies indicate that docosahexaenoic acid (DHA, a n-3 PUFA found in fish-oil) ... ...

    Abstract Low levels of n-3 poly-unsaturated fatty acids (n-3 PUFAs) and high levels of n-6 PUFAs in the blood circulation are associated with an increased risk for suicide. Clinical studies indicate that docosahexaenoic acid (DHA, a n-3 PUFA found in fish-oil) displays protective effects against suicide. It has recently been proposed that the activation of the transcription factor NRF2 might be the pharmacological activity that is common to current anti-suicidal medications. Oxidation products from fish oil, including those from DHA, are electrophiles that reversibly bind to a protein ‘KEAP1’, which acts as the molecular inhibitor of NRF2 and so indirectly promotes NRF2-transcriptional activity. In the majority of publications, the NRF2-stimulant effect of DHA is ascribed to the metabolite 4-hydroxyhexenal (4HHE). It is suggested to investigate whether 4HHE will display a therapeutically useful anti-suicidal efficacy.
    Keywords suicide prevention ; fish oil ; docosahexaenoic acid ; NRF2 ; 4-hydroxyhexenal ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Language English
    Publishing date 2022-06-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  8. Article: Novel Treatment Targets Based on Insights in the Etiology of Depression: Role of IL-6 Trans-Signaling and Stress-Induced Elevation of Glutamate and ATP.

    Kalkman, Hans O

    Pharmaceuticals (Basel, Switzerland)

    2019  Volume 12, Issue 3

    Abstract: Inflammation and psychological stress are risk factors for major depression and suicide. Both increase central glutamate levels and activate the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Both factors also affect the function ...

    Abstract Inflammation and psychological stress are risk factors for major depression and suicide. Both increase central glutamate levels and activate the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Both factors also affect the function of the chloride transporters, Na-K-Cl-cotransporter-1 (NKCC1) and K-Cl-cotransporter-2 (KCC2), and provoke interleukin-6 (IL-6) trans-signaling. This leads to measurable increases in circulating corticosteroids, catecholamines, anxiety, somatic and psychological symptoms, and a decline in cognitive functions. Recognition of the sequence of pathological events allows the prediction of novel targets for therapeutic intervention. Amongst others, these include blockade of the big-K potassium channel, blockade of the P2X4 channel, TYK2-kinase inhibition, noradrenaline α2B-receptor antagonism, nicotinic α7-receptor stimulation, and the Sgp130Fc antibody. A better understanding of downstream processes evoked by inflammation and stress also allows suggestions for tentatively better biomarkers (e.g., SERPINA3N, MARCKS, or
    Language English
    Publishing date 2019-07-29
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2193542-7
    ISSN 1424-8247
    ISSN 1424-8247
    DOI 10.3390/ph12030113
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: An Explanation for the Adiponectin Paradox

    Hans O. Kalkman

    Pharmaceuticals, Vol 14, Iss 1266, p

    2021  Volume 1266

    Abstract: The adipokine adiponectin improves insulin sensitivity. Functional signal transduction of adiponectin requires at least one of the receptors AdipoR1 or AdipoR2, but additionally the glycosyl phosphatidylinositol-anchored molecule, T-cadherin. ... ...

    Abstract The adipokine adiponectin improves insulin sensitivity. Functional signal transduction of adiponectin requires at least one of the receptors AdipoR1 or AdipoR2, but additionally the glycosyl phosphatidylinositol-anchored molecule, T-cadherin. Overnutrition causes a reduction in adiponectin synthesis and an increase in the circulating levels of the enzyme glycosyl phosphatidylinositol-phospholipase D (GPI-PLD). GPI-PLD promotes the hydrolysis of T-cadherin. The functional consequence of T-cadherin hydrolysis is a reduction in adiponectin sequestration by responsive tissues, an augmentation of adiponectin levels in circulation and a (further) reduction in signal transduction. This process creates the paradoxical situation that adiponectin levels are augmented, whereas the adiponectin signal transduction and insulin sensitivity remain strongly impaired. Although both hypoadiponectinemia and hyperadiponectinemia reflect a situation of insulin resistance, the treatments are likely to be different.
    Keywords insulin resistance ; glycosyl phosphatidylinositol-phospholipase D ; type 2 diabetes ; T-cadherin ; hyperadiponectinemia ; Medicine ; R ; Pharmacy and materia medica ; RS1-441
    Subject code 571
    Language English
    Publishing date 2021-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  10. Article ; Online: The Association Between Vascular Inflammation and Depressive Disorder. Causality, Biomarkers and Targeted Treatment

    Hans O. Kalkman

    Pharmaceuticals, Vol 13, Iss 92, p

    2020  Volume 92

    Abstract: Diabetes, obesity, atherosclerosis, and myocardial infarction are frequently co-morbid with major depressive disorder. In the current review, it is argued that vascular inflammation is a factor that is common to all disorders and that an endothelial ... ...

    Abstract Diabetes, obesity, atherosclerosis, and myocardial infarction are frequently co-morbid with major depressive disorder. In the current review, it is argued that vascular inflammation is a factor that is common to all disorders and that an endothelial dysfunction of the blood-brain barrier could be involved in the induction of depression symptoms. Biomarkers for vascular inflammation include a high plasma level of C-reactive protein, soluble cell-adhesion molecules, von Willebrand factor, aldosterone, and proinflammatory cytokines like interleukin-6 or tumor necrosis factor α. A further possible biomarker is flow-mediated dilation of the brachial artery. Treatment of vascular inflammation is expected to prevent or to reduce symptoms of depression. Several tentative treatments for this form of depression can be envisioned: eicosapentaenoic acid (EPA), valproate, Vagus -nerve stimulation, nicotinic α7 agonists, and agonists of the cannabinoid CB 2 -receptor.
    Keywords systemic low-grade inflammation ; oxidative stress ; geriatric depression ; gender differences ; leptin ; EKODE ; Medicine ; R ; Pharmacy and materia medica ; RS1-441
    Subject code 610
    Language English
    Publishing date 2020-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top