Publications by authors named "Lee Ming Tatt"

Introduction: The α6 subunit-containing GABA receptors (α6GABARs) are highly expressed in the trigeminal ganglia (TG), the sensory hub of the trigeminovascular system (TGVS). Hypo-GABAergic transmission in the TG was reported to contribute to migraine-related behavioral and histopathological phenotypes. Previously, we found that Compound 6, an α6GABAR-selective positive allosteric modulator (PAM), significantly alleviated TGVS activation-induced peripheral and central sensitization in a capsaicin-induced migraine-mimicking model.

View Article and Find Full Text PDF
Article Synopsis
  • * A study evaluated the effects of vitamin E compounds—α-tocopherol and tocotrienol-rich palm oil extract—on anxiety and depressive behaviors in mice with estrogen deficiency, finding that these compounds had positive effects on mood-related behaviors.
  • * The results indicated that both supplements reduced stress hormone levels and improved symptoms, suggesting they could be a promising new treatment option for menopause-related mood disorders, potentially influencing the hypothalamic-pituitary-adrenal (HPA) axis.
View Article and Find Full Text PDF
Article Synopsis
  • Atopic dermatitis (AD) is a chronic skin condition with no cure, and this study investigated the effectiveness of a compound called tHGA as a treatment for AD-like symptoms in mice.
  • Male BALB/c mice were exposed to DNCB to induce AD-like skin lesions and were treated with various doses of tHGA either orally or topically over a set period.
  • The results showed that both methods of administration significantly improved symptoms such as itching, skin thickness, and inflammation, indicating that tHGA has potential as a therapeutic option for managing AD.
View Article and Find Full Text PDF
Article Synopsis
  • Gynostemma pentaphyllum is a creeping herb known for its medicinal use in traditional oriental medicine, primarily due to gypenosides, its main bioactive compounds.
  • Research suggests that gypenosides may have therapeutic effects on various neuropsychiatric disorders, including depression and Alzheimer's, by influencing key signaling pathways in the nervous system.
  • Despite promising preclinical results, there's a significant lack of clinical studies on gypenosides, indicating a need for further research to understand their effects and mechanisms in humans for potential health benefits.
View Article and Find Full Text PDF

Perimenopausal depression, occurring shortly before or after menopause, is characterized by symptoms such as emotional depression, anxiety, and stress, often accompanied by endocrine dysfunction, particularly hypogonadism and senescence. Current treatments for perimenopausal depression primarily provide symptomatic relief but often come with undesirable side effects. The development of agents targeting the specific pathologies of perimenopausal depression has been relatively slow.

View Article and Find Full Text PDF

The prevalence of house dust mite (HDM) allergy, especially in Asian countries with rapid urbanization, has been increasing. House dust mites thrive in places with relatively high humidity. With the combination of climate change, naturally high humidity, and urbanization, tropical countries like Malaysia are becoming a hotspot for HDM allergy fast.

View Article and Find Full Text PDF

Objective: The SLIT and NTRK-like 1 (SLITRK1) gene mutation and striatal cholinergic interneurons (ChIs) loss are associated with Tourette syndrome (TS). ChIs comprise only 1 to 2% of striatal neurons but project widely throughout the stratum to impact various striatal neurotransmission, including TS-related dopaminergic transmission. Here, we link striatal Slitrk1, ChI function, and dopaminergic transmission and their associations with TS-like tic behaviors.

View Article and Find Full Text PDF

Chronic pain conditions within clinical populations are correlated with a high incidence of depression, and researchers have reported their high rate of comorbidity. Clinically, chronic pain worsens the prevalence of depression, and depression increases the risk of chronic pain. Individuals suffering from chronic pain and depression respond poorly to available medications, and the mechanisms underlying the comorbidity of chronic pain and depression remain unknown.

View Article and Find Full Text PDF

Interferons (IFNs) are important in controlling the innate immune response to viral infections. Besides that, studies have found that IFNs also have antimicrobial, antiproliferative/antitumor and immunomodulatory effects. IFNs are divided into Type I, II and III.

View Article and Find Full Text PDF

Ethanol has been shown to suppress essential tremor (ET) in patients at low-to-moderate doses, but its mechanism(s) of action remain unknown. One of the ET hypotheses attributes the ET tremorgenesis to the over-activated firing of inferior olivary neurons, causing synchronic rhythmic firings of cerebellar Purkinje cells. Purkinje cells, however, also receive excitatory inputs from granule cells where the α6 subunit-containing GABA receptors (α6GABARs) are abundantly expressed.

View Article and Find Full Text PDF

Recreational use of alcohol is a social norm in many communities worldwide. Alcohol use in moderation brings pleasure and may protect the cardiovascular system. However, excessive alcohol consumption or alcohol abuse are detrimental to one's health.

View Article and Find Full Text PDF

Ethnopharmacological Relevance: Allergy is mediated by the crosslinking of immunoglobulins (Ig) -E or -G to their respective receptors, which degranulates mast cells, macrophages, basophils, or neutrophils, releasing allergy-causing mediators. The removal of these mediators such as histamine, platelet-activating factor (PAF) and interleukins (ILs) released by effector cells will alleviate allergy. Clinacanthus nutans (C.

View Article and Find Full Text PDF

Phosphodiesterase 1B (PDE1B) and PDE10A are dual-specificity PDEs that hydrolyse both cyclic adenosine monophosphate and cyclic guanosine monophosphate, and are highly expressed in the striatum. Several reports have suggested that PDE10A inhibitors may present a promising approach for the treatment of positive symptoms of schizophrenia, whereas PDE1B inhibitors may present a novel mechanism to modulate cognitive deficits. Previously, we have reported a novel dual inhibitor of PDE1B and PDE10A, compound 2 [(3-fluorophenyl)(2-methyl-2,3-dihydro-4H-benzo[b][1,4]oxazin-4-yl)methanone] which has shown inhibitory activity for human recombinant PDE1B and PDE10A in vitro.

View Article and Find Full Text PDF

ABT-199 (venetoclax) is the first-in-class selective B-cell lymphoma 2 (BCL2) inhibitor, which is known to be ineffective towards liver cancer cells. Here, we investigated the efficacy and the underlying molecular processes of the sensitization effect of kaempferol isolated from persimmon leaves (KPL) on the ABT-199-resistant HepG2 cells. The effects of various doses of KPL coupled with ABT-199 on the proliferation of HepG2 cells and on the H22 liver tumor-bearing mouse model were examined, as well as the underlying mechanisms.

View Article and Find Full Text PDF

Osteoporosis, or bone loss, is a disease that affects many women globally. As life expectancy increases, the risk of osteoporosis in women also increases, too, and this will create a burden on the healthcare and economic sectors of a country. Osteoporosis was once thought to be a disease that would occur only after menopause.

View Article and Find Full Text PDF

Rationale: Clinical reports reveal that scopolamine, an acetylcholine muscarinic receptor antagonist, exerts rapid antidepressant effects in depressed patients, but the mechanisms underlying the therapeutic effects have not been fully identified.

Objectives: The present study examines the cellular mechanisms by which scopolamine produces antidepressant-like effects through its action in the ventrolateral midbrain periaqueductal gray (vlPAG).

Methods: We used a well-established mouse model of depression induced by chronic restraint stress (CRS) exposure for 14 days.

View Article and Find Full Text PDF

Major depressive disorder (MDD) is a common neuropsychiatric disorder affecting the mood and mental well-being. Its pathophysiology remains elusive due to the complexity and heterogeneity of this disorder that affects millions of individuals worldwide. Chronic stress is frequently cited as the one of the risk factors for MDD.

View Article and Find Full Text PDF

Nanomedicines emerged from nanotechnology and have been introduced to bring advancements in treating multiple diseases. Nano-phytomedicines are synthesized from active phytoconstituents or plant extracts. Advancements in nanotechnology also help in the diagnosis, monitoring, control, and prevention of various diseases.

View Article and Find Full Text PDF

GABA receptors containing α6 subunits (α6GABARs) in the cerebellum have -been implicated in schizophrenia. It was reported that the GABA synthesizing enzymes were downregulated whereas α6GABARs were upregulated in postmortem cerebellar tissues of patients with schizophrenia and in a rat model induced by chronic phencyclidine (PCP). We have previously demonstrated that pyrazoloquinolinone Compound 6, an α6GABAR-highly selective positive allosteric modulator (PAM), can rescue the disrupted prepulse inhibition (PPI) induced by methamphetamine (METH), an animal model mimicking the sensorimotor gating deficit based on the hyper-dopaminergic hypothesis of schizophrenia.

View Article and Find Full Text PDF

Phosphodiesterase10A (PDE10A) is a potential therapeutic target for the treatment of several neurodegenerative disorders. Thus, extensive efforts of medicinal chemists have been directed toward developing potent PDE10A inhibitors with minimal side effects. However, PDE10A inhibitors are not approved as a treatment for neurodegenerative disorders, possibly due to the lack of research in this area.

View Article and Find Full Text PDF

GABA receptors containing the 6 subunit are highly expressed in cerebellar granule cells and less abundantly in many other neuronal and peripheral tissues. Here, we for the first time summarize their importance for the functions of the cerebellum and the nervous system. The cerebellum is not only involved in motor control but also in cognitive, emotional, and social behaviors.

View Article and Find Full Text PDF

The use of opioids in pain management is hampered by the emergence of analgesic tolerance, which leads to increased dosing and side effects, both of which have contributed to the opioid epidemic. One promising potential approach to limit opioid analgesic tolerance is activating the endocannabinoid system in the CNS, via activation of CB receptors in the descending pain inhibitory pathway. In this review, we first discuss preclinical and clinical evidence revealing the potential of pharmacological activation of CB receptors in modulating opioid tolerance, including activation by phytocannabinoids, synthetic CB receptor agonists, endocannabinoid degradation enzyme inhibitors, and recently discovered positive allosteric modulators of CB receptors.

View Article and Find Full Text PDF

Migraine is caused by hyperactivity of the trigeminovascular system, where trigeminal ganglia (TG) play an important role. This hyperactivity might originate from an underfunctional GABAergic system in TG. To investigate this possibility, we adapted a mouse model of migraine by inducing migraine-like grimaces in male mice via repeated injections of nitroglycerin (NTG, 10 mg/kg, i.

View Article and Find Full Text PDF