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Journal of Neuro-oncology Jun 2024Functioning pituitary adenomas (FPAs) include most frequently prolactinomas, somatotroph or corticotroph adenomas, while thyrotroph and gonadotroph adenomas are very... (Review)
Review
CONTEXT
Functioning pituitary adenomas (FPAs) include most frequently prolactinomas, somatotroph or corticotroph adenomas, while thyrotroph and gonadotroph adenomas are very rare. Despite their benign histological nature (aggressive tumors are rare and malignant ones exceptional), FPAs could cause significant morbidity and increased mortality due to complications associated with hormonal excess syndromes and/or mass effect leading to compression of adjacent structures. This mini review will focus on the increasing role of medical therapy in the multimodal treatment, which also includes transsphenoidal surgery (TSS) and radiotherapy.
EVIDENCE SYNTHESIS
Most patients with prolactinomas are treated only with medications, but surgery could be considered for some patients in a specialized pituitary center, if higher chances of cure. Dopamine agonists, especially cabergoline, are efficient in reducing tumor size and normalizing prolactin. TSS is the first-line treatment for all other FPAs, but most patients require complex adjuvant treatment, including a combination of therapeutic approaches. Medical therapy is the cornerstone of treatment in all patients after unsuccessful surgery or when surgery cannot be offered and includes somatostatin receptor ligands and dopamine agonists (almost all FPAs), growth hormone receptor antagonists (acromegaly), adrenal steroidogenesis inhibitors and glucocorticoid receptor blockers (Cushing's disease). Novel medical treatments, especially for acromegaly and Cushing's disease are under research.
CONCLUSIONS
An enlarged panel of effective drugs available with increased knowledge of predictive factors for response and/or adverse effects will enhance the possibility to offer a more individualized treatment. This would not only improve disease control and prognosis, but also quality of life.
Topics: Humans; Pituitary Neoplasms; Adenoma; Combined Modality Therapy; Clinical Trials as Topic
PubMed: 38760632
DOI: 10.1007/s11060-024-04670-x -
Cureus Apr 2024Alzheimer's disease (AD) is the most common neurodegenerative condition and a form of dementia encountered in medical practice. Despite many proposed and attempted... (Review)
Review
Alzheimer's disease (AD) is the most common neurodegenerative condition and a form of dementia encountered in medical practice. Despite many proposed and attempted treatments, this disease remains a major puzzle in the public health systems worldwide. The initial part of this article provides an overview and illustration of the primary mechanisms responsible for neuronal damage in AD. Subsequently, it offers a critical evaluation of the most noteworthy studies on pharmacological therapy for AD and outlines recent advancements and novel approaches to managing this condition. Main properties, categorization, Food and Drug Administration (FDA) status, mechanisms of action, benefits, and common side effects of the classical and the most recently proposed pharmacological treatments for AD are described. The conventional pharmacological agents revised comprise cholinesterase inhibitors, monoclonal antibodies, and other therapies, such as memantine, valproic acid, and rosiglitazone. The innovative reviewed pharmacological agents comprise the monoclonal antibodies: donanemab, gantenerumab, solanezumab, bapineuzumab, crenezumab, and semorinemab. Nutritional supplements such as alpha-tocopherol (vitamin E) and caprylidene are also revised. Tau and amyloid-targeting treatments include methylthioninium moiety (MT), leuco-methylthioninium bis (LMTM), an oxidized form of MT, and tramiprosate, which inhibits the beta-amyloid (Aβ) monomer aggregation into toxic oligomers. Antidiabetic and anti-neuroinflammation drugs recently proposed for AD treatment are discussed. The antidiabetic drugs include NE3107, an anti-inflammatory and insulin sensitizer, and the diabetes mainstream drug metformin. The anti-neuroinflammatory AD therapies include the use of sodium oligomannate (GV-971), infusions with intravenous immunoglobulin aiming to decrease plasma levels of the constituents of Aβ plaques, and masitinib, a tyrosine kinase inhibitor that impacts mast and microglia cells. Additional anti-inflammatory agents being currently tested in phase-2 clinical trials, such as atomoxetine (selective norepinephrine reuptake inhibitor), losartan (angiotensin 2 receptor agonist), genistein (anti-inflammatory isoflavone neuroprotective agent), trans-resveratrol (polyphenol antioxidant plant estrogen), and benfotiamine (synthetic thiamine precursor), were reviewed. Lastly, drugs targeting Alzheimer's-associated symptoms, such as brexpiprazole (serotonin dopamine activity modulator) and suvorexant (orexin receptor antagonist), respectively, used for agitation and insomnia in AD patients, are reviewed. As experimental investigations and clinical research progress, there is a possibility that a combination of newly tested medications and traditional ones may emerge as a promising treatment option for AD in the future.
PubMed: 38756263
DOI: 10.7759/cureus.58416 -
Neuroscience and Biobehavioral Reviews Jul 2024Continuous treatment with drugs is a crucial requirement for managing various clinical conditions, including chronic pain and neuropsychiatric disorders such as... (Review)
Review
Continuous treatment with drugs is a crucial requirement for managing various clinical conditions, including chronic pain and neuropsychiatric disorders such as depression or schizophrenia. Associative learning processes, i.e. Pavlovian conditioning, can play an important role for the effects of drugs and could open new avenues for optimizing patient treatment. In this narrative literature review, we summarize available data in experimental animals regarding the behaviorally conditioned effects of psychostimulants such as d-amphetamine and cocaine, the dopamine receptor agonist apomorphine, the dopamine receptor antagonist haloperidol, morphine and antidepressant drugs. In each section, the drug under discussion is briefly introduced, followed by a detailed examination of conditioning features, including doses and dosing regimens, characteristics of the conditioning process such as test environments or specific conditioned stimuli, testing and conditioned response characteristics, possible extinction or reconditioning or reversal training, neural mechanisms, and finally, the potential clinical relevance of the research area related to the drug. We focus on key outcomes, delve into methodical issues, identify gaps in current knowledge, and suggest future research directions.
Topics: Animals; Psychotropic Drugs; Humans; Conditioning, Classical; Behavior, Animal
PubMed: 38754716
DOI: 10.1016/j.neubiorev.2024.105721 -
Neurochemistry International Jul 2024Although the output of the lateral habenula (LHb) controls the activity of midbrain dopaminergic and serotonergic systems, which are implicated in the pathophysiology of...
Although the output of the lateral habenula (LHb) controls the activity of midbrain dopaminergic and serotonergic systems, which are implicated in the pathophysiology of anxiety, it is not clear the role of LHb 5-HT receptors in regulation of anxiety-like behaviors, particularly in Parkinson's disease-related anxiety. In this study, unilateral 6-hydroxydopamine lesions of the substantia nigra pars compacta in rats induced anxiety-like behaviors, led to decreased normalized δ power and increased normalized θ power in the LHb, and decreased dopamine (DA) level in the prelimbic cortex (PrL) compared with sham rats. Down-regulation of LHb 5-HT receptors by RNA interference produced anxiety-like effects, decreased normalized δ power and increased normalized θ power in the LHb in both sham and lesioned rats. Further, intra-LHb injection of 5-HT receptor agonist CP93129 induced anxiolytic-like responses, increased normalized δ power and decreased normalized θ power in the LHb, and increased DA and serotonin (5-HT) release in the PrL; conversely, 5-HT receptor antagonist SB216641 produced anxiety-like effects, decreased normalized δ power and increased normalized θ power in the LHb, and decreased DA and 5-HT release in the PrL in sham and lesioned rats. Additionally, effects of CP93129 and SB216641 on the behaviors, normalized δ and θ power in the LHb, and DA and 5-HT release in the PrL were decreased in lesioned rats, which were consistent with down-regulation of LHb 5-HT receptors after DA depletion. Collectively, these findings suggest that 5-HT receptors in the LHb are involved in the regulation of anxiety-like behaviors.
Topics: Animals; Habenula; Receptor, Serotonin, 5-HT1B; Male; Anxiety; Rats; Rats, Sprague-Dawley; Oxidopamine; Parkinsonian Disorders; Dopamine; Behavior, Animal
PubMed: 38750961
DOI: 10.1016/j.neuint.2024.105766 -
European Journal of Drug Metabolism and... Jul 2024A model-informed drug development (MIDD) approach was implemented for paliperidone palmitate (PP) 6-month (PP6M) clinical development, using pharmacokinetics and...
BACKGROUND AND OBJECTIVE
A model-informed drug development (MIDD) approach was implemented for paliperidone palmitate (PP) 6-month (PP6M) clinical development, using pharmacokinetics and pharmacokinetic/pharmacodynamic model-based simulations.
METHODS
PP6M pharmacokinetics were simulated by extending the PP 3-month (PP3M) pharmacokinetic model to account for increased injection volume, and hence dose. Contribution of the MIDD approach to the design of the pivotal PP6M phase-3 study (PP6M/PP3M noninferiority study, NCT03345342) investigating schizophrenia relapse rates was twofold: (1) PP6M dose selection, and (2) hypothesis generation that lower trough concentrations (C) associated with PP6M, relative to PP3M, were not associated with lower efficacy, which was to be evaluated in the phase-3 study. Moreover, accompanied by an intense sampling scheme to adequately characterize paliperidone pharmacokinetics and to elucidate the potential relationship between concentration and safety/efficacy, the bridging strategy eliminated the need for additional phase-1/phase-2 clinical studies.
RESULTS
Using a MIDD bridging strategy, PP6M doses were selected that, compared with PP3M, were expected to have a similar range of exposures and a noninferior relapse rate and safety profile. Clinical data from PP6M/PP3M noninferiority study confirmed that PP6M, compared with PP3M, had a similar range of exposures (T'jollyn et al. in Eur J Drug Metab Pharmacokinet 2024), as well as a noninferior relapse rate and safety profile (this manuscript).
CONCLUSIONS
Consistency of the MIDD approach with observed clinical outcomes confirmed the hypothesis that lower C did not lead to increased relapse rates at the doses administered. Although higher paliperidone peak concentrations are achieved with corresponding doses of PP6M relative to PP3M in the phase-3 clinical study, types and incidences of treatment-related adverse events were comparable between PP6M and PP3M groups and no new safety concerns emerged for PP6M (Najarian et al. in Int J Neuropsychopharmacol 25(3):238-251, 2022).
Topics: Paliperidone Palmitate; Humans; Schizophrenia; Antipsychotic Agents; Models, Biological; Drug Administration Schedule; Adult; Male; Female; Drug Development; Computer Simulation
PubMed: 38750386
DOI: 10.1007/s13318-024-00900-9 -
Pakistan Journal of Pharmaceutical... Jan 2024Aripiprazole (ARI), an antipsychotic having low solubility and stability. To overcome this, formation of binary and ternary using inclusion complexes of... (Comparative Study)
Comparative Study
Aripiprazole (ARI), an antipsychotic having low solubility and stability. To overcome this, formation of binary and ternary using inclusion complexes of Methyl-β-cyclodextrin (MβCD) /Hydroxy propyl beta cyclodextrin (HPβCD) and L-Arginine (ARG)/ Lysine (LYS) are analyzed by dissolution testing and phase stability study along with their complexation efficacy and solubility constants made by physical mixing. Inclusion complexes with ARG were better than LYS and prepared by solvent evaporation and lyophilization method as well. They are characterized by Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (AT-FTIR), X-ray powder diffractometry (XRD), Differential Scanning Calorimetry (DSC), Scanning electron microscopy (SEM) and Thermal gravimetric analysis (TGA). The bond shifting in AT-FTIR confirmed the molecular interactions between host and guest molecules. The SEM images also confirmed a complete change of drug morphology in case of ternary inclusion complexes prepared by lyophilization method for both the polymers. ARI: MβCD: ARG when used in the specific molar ratio of 1:1:0.27 by prepared by lyophilization method has 18 times best solubility while ARI:HPβCD:ARG was 7 times best solubility than pure drug making MβCD a better choice than HPβCD. Change in the molar ratio will cause loss of stability or solubility. Solvent evaporation gave significant level of solubility but less stability.
Topics: Aripiprazole; Arginine; Solubility; beta-Cyclodextrins; 2-Hydroxypropyl-beta-cyclodextrin; Lysine; Spectroscopy, Fourier Transform Infrared; Calorimetry, Differential Scanning; X-Ray Diffraction; Freeze Drying; Antipsychotic Agents; Drug Stability; Microscopy, Electron, Scanning; Drug Compounding; Chemistry, Pharmaceutical
PubMed: 38747276
DOI: No ID Found -
Experimental Cell Research Jun 2024Dopamine D2 receptors (D2Rs) play crucial roles in regulating diverse physiological functions of the central nervous system and peripheral organs. D2Rs are also...
Dopamine D2 receptors (D2Rs) play crucial roles in regulating diverse physiological functions of the central nervous system and peripheral organs. D2Rs are also expressed in mammary glands. However, which cell types express D2Rs and whether they are involved in milk production remains unclear. The present findings revealed that D2Rs are expressed in the apical regions of the lateral membranes of mammary epithelial cells (MECs) in lactating mice. We also investigated the effects of the D2R agonist bromocriptine and/or antagonist domperidone on intracellular cAMP levels, milk protein production, and apoptosis in a lactation culture model of MECs that produce major milk components like lactating MECs in vivo. We found that bromocriptine decreased intracellular cAMP levels, whereas domperidone dose-dependently neutralized this effect. Bromocriptine also inhibited casein and lactoferrin production and suppressed activities of STAT5 and glucocorticoid receptors (GRs). Domperidone neutralized the inhibition of casein production as well as STAT5 and GR inactivation induced by bromocriptine. Furthermore, D2R activation by bromocriptine induced apoptosis and inactivated ERK, a signaling molecule responsible for promoting cell proliferation and survival. Domperidone attenuated ERK inactivation and apoptosis induced by bromocriptine. These findings suggest that D2Rs play regulatory roles in milk protein production and apoptosis in MECs.
Topics: Animals; Female; Mice; Apoptosis; Bromocriptine; Cells, Cultured; Cyclic AMP; Domperidone; Epithelial Cells; Lactation; Mammary Glands, Animal; Milk Proteins; Receptors, Dopamine D2; STAT5 Transcription Factor
PubMed: 38740167
DOI: 10.1016/j.yexcr.2024.114090 -
Tremor and Other Hyperkinetic Movements... 2024Opsoclonus is a rare disorder characterized by conjugate multidirectional, horizontal, vertical, and torsional saccadic oscillations, without intersaccadic interval,...
BACKGROUND
Opsoclonus is a rare disorder characterized by conjugate multidirectional, horizontal, vertical, and torsional saccadic oscillations, without intersaccadic interval, resulting from dysfunction within complex neuronal pathways in the brainstem and cerebellum. While most cases of opsoclonus are associated with autoimmune or paraneoplastic disorders, infectious agents, trauma, or remain idiopathic, opsoclonus can also be caused by medications affecting neurotransmission. This review was prompted by a case of opsoclonus occurring in a patient with Multiple System Atrophy, where amantadine, an NMDA-receptor antagonist, appeared to induce opsoclonus.
METHODS
Case report of a single patient and systematized review of toxic/drug-induced opsoclonus, selecting articles based on predefined criteria and assessing the quality of included studies.
RESULTS
The review included 30 articles encompassing 158 cases of toxic/drug-induced opsoclonus. 74% of cases were attributed to bark scorpion poisoning, followed by 9% of cases associated with chlordecone intoxication. The remaining cases were due to various toxics/drugs, highlighting the involvement of various neurotransmitters, including acetylcholine, glutamate, GABA, dopamine, glycine, and sodium channels, in the development of opsoclonus.
CONCLUSION
Toxic/drug-induced opsoclonus is very rare. The diversity of toxics/drugs impacting different neurotransmitter systems makes it challenging to define a unifying mechanism, given the intricate neuronal pathways underlying eye movement physiology and opsoclonus pathophysiology.
Topics: Humans; Male; Amantadine; Multiple System Atrophy; Ocular Motility Disorders; Aged
PubMed: 38737300
DOI: 10.5334/tohm.832 -
Journal of Family Medicine and Primary... Mar 2024This is a report of a series of three cases of trazodone-induced oral lingual dyskinesias. Each case demonstrated a distinct pattern of the development of this...
This is a report of a series of three cases of trazodone-induced oral lingual dyskinesias. Each case demonstrated a distinct pattern of the development of this dyskinesia after trazodone exposure for several months. All cases showed abrupt cessation of the movement disorder when the drug was discontinued. Two of the three cases had no prior exposure to any dopamine-blocking agents. One of the three had a distant exposure to a dopamine antagonist. Trazodone has a mechanism of action that can account for both the development and treatment of dyskinetic movements. This article will discuss proposed mechanisms for trazodone's action with an emphasis on case reports of dystonic movements being more prevalent in the elderly.
PubMed: 38736787
DOI: 10.4103/jfmpc.jfmpc_645_23 -
Neurobiology of Learning and Memory Jul 2024Systemic manipulations that enhance dopamine (DA) transmission around the time of fear extinction can strengthen fear extinction and reduce conditioned fear relapse....
Systemic manipulations that enhance dopamine (DA) transmission around the time of fear extinction can strengthen fear extinction and reduce conditioned fear relapse. Prior studies investigating the brain regions where DA augments fear extinction focus on targets of mesolimbic and mesocortical DA systems originating in the ventral tegmental area, given the role of these DA neurons in prediction error. The dorsal striatum (DS), a primary target of the nigrostriatal DA system originating in the substantia nigra (SN), is implicated in behaviors beyond its canonical role in movement, such as reward and punishment, goal-directed action, and stimulus-response associations, but whether DS DA contributes to fear extinction is unknown. We have observed that chemogenetic stimulation of SN DA neurons during fear extinction prevents the return of fear in contexts different from the extinction context, a form of relapse called renewal. This effect of SN DA stimulation is mimicked by a DA D1 receptor (D1R) agonist injected into the DS, thus implicating DS DA in fear extinction. Different DS subregions subserve unique functions of the DS, but it is unclear where in the DS D1R agonist acts during fear extinction to reduce renewal. Furthermore, although fear extinction increases neural activity in DS subregions, whether neural activity in DS subregions is causally involved in fear extinction is unknown. To explore the role of DS subregions in fear extinction, adult, male Long-Evans rats received microinjections of either the D1R agonist SKF38393 or a cocktail consisting of GABA/GABA receptor agonists muscimol/baclofen selectively into either dorsomedial (DMS) or dorsolateral (DLS) DS subregions immediately prior to fear extinction, and extinction retention and renewal were subsequently assessed drug-free. While increasing D1R signaling in the DMS during fear extinction did not impact fear extinction retention or renewal, DMS inactivation reduced later renewal. In contrast, DLS inactivation had no effect on fear extinction retention or renewal but increasing D1R signaling in the DLS during extinction reduced fear renewal. These data suggest that DMS and DLS activity during fear extinction can have opposing effects on later fear renewal, with the DMS promoting renewal and the DLS opposing renewal. Mechanisms through which the DS could influence the contextual gating of fear extinction are discussed.
Topics: Animals; Fear; Extinction, Psychological; Male; Rats; Corpus Striatum; Receptors, Dopamine D1; Dopamine Agonists; Conditioning, Classical; Dopaminergic Neurons; Substantia Nigra; Rats, Long-Evans; Dopamine
PubMed: 38735637
DOI: 10.1016/j.nlm.2024.107937