One-Step Biosynthesis of α-Keto-γ-Methylthiobutyric Acid from L-Methionine by an Escherichia coli Whole-Cell Biocatalyst Expressing an Engineered L-Amino Acid Deaminase from Proteus vulgaris
α-Keto-γ-methylthiobutyric acid (KMTB), a keto derivative of -methionine, has great potential for use as an alternative to -methionine in the poultry industry and as an anti-cancer drug. This study developed an environment friendly process ...
2-Keto-4-(Methylthio)Butyric Acid (Keto Analog of Methionine) Is a Safe and Efficacious Precursor of l-Methionine in Chicks | The Journal of Nutrition | Oxford Academic
Abstract. Relative bioefficacy and toxicity of Met precursor compounds were investigated in young chicks. The effectiveness of dl-Met and 2-keto-4-(methylthio)b
One-Step Biosynthesis of α-Keto-γ-Methylthiobutyric Acid from L-Methionine by an Escherichia coli Whole-Cell Biocatalyst Expressing an Engineered L-Amino Acid Deaminase from Proteus vulgaris
α-Keto-γ-methylthiobutyric acid (KMTB), a keto derivative of l-methionine, has great potential for use as an alternative to l-methionine in the poultry industry and as an anti-cancer drug. This study developed an environment friendly process for KMTB production from l-methionine by an Escherichia coli whole-cell biocatalyst expressing an engineered l-amino acid deaminase (l-AAD) from Proteus vulgaris. We first overexpressed the P. vulgaris l-AAD in E. coli BL21 (DE3) and further optimized the whole-cell transformation process. The maximal molar conversion ratio of l-methionine to KMTB was 71.2% (mol/mol) under the optimal conditions (70 g/L l-methionine, 20 g/L whole-cell biocatalyst, 5 mM CaCl2, 40°C, 50 mM Tris-HCl [pH 8.0]). Then, error-prone polymerase chain reaction was used to construct P. vulgaris l-AAD mutant libraries. Among approximately 104 mutants, two mutants bearing lysine 104 to arginine and alanine 337 to serine substitutions showed 82.2% and 80.8% molar conversion ratios, respectively. Furthermore, the combination of these mutations enhanced the catalytic activity and molar conversion ratio by 1.3-fold and up to 91.4% with a KMTB concentration of 63.6 g/L. Finally, the effect of immobilization on whole-cell transformation was examined, and the immobilized whole-cell biocatalyst with Ca2+ alginate increased reusability by 41.3% compared to that of free cell production. Compared with the traditional multi-step chemical synthesis, our one-step biocatalytic production of KMTB has an advantage in terms of environmental pollution and thus has great potential for industrial KMTB production.
Cross-fostering effect on postnatal development of rat pups exposed to methamphetamine during gestation and preweaning periods - PubMed
There are studies showing that drug abuse during pregnancy may have a long-term effect on progeny of drug-abusing mothers. Our previous work demonstrated that prenatal and/or postnatal methamphetamine injections impair maternal behavior. The purpose of the present study was to assess the effect of p …
Molecular Characterization of an Arachidonic Acid Epoxygenase in Rat Brain Astrocytes | Stroke
Background and Purpose Brain parenchymal tissue metabolizes arachidonic acid (AA) via the cytochrome P450 (P450) epoxygenase to epoxyeicosatrienoic acids (EETs). EETs dilate cerebral arterioles and e
Role of Cytochrome P450 Epoxygenases, Soluble Epoxide Hydrolase, and Epoxyeicosatrienoic Acids in Metabolic Diseases | Advances in Nutrition | Oxford Academic
ABSTRACT. Metabolic diseases are associated with an increased risk of developing cardiovascular disease. The features comprising metabolic diseases include obes
Molecular mechanisms underlying the actions of arachidonic acid-derived prostaglandins on peripheral nociception | Journal of Neuroinflammation | Full Text
Arachidonic acid-derived prostaglandins not only contribute to the development of inflammation as intercellular pro-inflammatory mediators, but also promote the excitability of the peripheral somatosensory system, contributing to pain exacerbation. Peripheral tissues undergo many forms of diseases that are frequently accompanied by inflammation. The somatosensory nerves innervating the inflamed areas experience heightened excitability and generate and transmit pain signals. Extensive studies have been carried out to elucidate how prostaglandins play their roles for such signaling at the cellular and molecular levels. Here, we briefly summarize the roles of arachidonic acid-derived prostaglandins, focusing on four prostaglandins and one thromboxane, particularly in terms of their actions on afferent nociceptors. We discuss the biosynthesis of the prostaglandins, their specific action sites, the pathological alteration of the expression levels of related proteins, the neuronal outcomes of receptor stimulation, their correlation with behavioral nociception, and the pharmacological efficacy of their regulators. This overview will help to a better understanding of the pathological roles that prostaglandins play in the somatosensory system and to a finding of critical molecular contributors to normalizing pain.
Antipyretic Therapy: Physiologic Rationale, Diagnostic Implications, and Clinical Consequences | Pain Medicine | JAMA Internal Medicine | JAMA Network
Various treatments have been used to suppress fever since antiquity. Surprisingly, few studies have been performed to ascertain the physiologic consequences of antipyresis and validate the rationale behind such therapy. More importantly, it has not been established conclusively that the benefits of...
Antipyretics: mechanisms of action and clinical use in fever suppression - The American Journal of Medicine
Fever is a complex physiologic response triggered by infectious or aseptic stimuli. Elevations in body temperature occur when concentrations of prostaglandin E2 (PGE2) increase within certain areas of the brain. These elevations alter the firing rate of neurons that control thermoregulation in the hypothalamus. Although fever benefits the nonspecific immune response to invading microorganisms, it is also viewed as a source of discomfort and is commonly suppressed with antipyretic medication. Antipyretics such as aspirin have been widely used since the late 19th century, but the mechanisms by which they relieve fever have only been characterized in the last few decades.
Neural Mechanisms of Inflammation-Induced Fever - Anders Blomqvist, David Engblom, 2018
Fever is a common symptom of infectious and inflammatory disease. It is well-established that prostaglandin E2 is the final mediator of fever, which by binding ...
Antipyretic effectiveness of intravenous ketorolac tromethamine - PubMed
We assessed the antipyretic effectiveness of intravenously administered ketorolac tromethamine in the febrile adult. A double-blind placebo controlled trial enrolling a convenience sample of febrile (T > 38.0 degrees C, oral) patients (18-65 years old) randomized to receive either 0.5 mg/kg (max …
Prenatal and perinatal factors influencing nociception, addiction and behavior during ontogenetic development - PubMed
This review, which summarizes our findings concerning the long-term effects of pre-, peri- and postnatal factors affecting development, nociception and sensorimotor functions, focuses on three areas: 1) perinatal factors influencing nociception in adult rats were examined in rats with hippocampal le …
VMAT2: a dynamic regulator of brain monoaminergic neuronal function interacting with drugs of abuse
The monoaminergic neuron, in particular the dopaminergic neuron, is central to mediating the hedonic and addictive properties of drugs of abuse. The effects of amphetamine (AMPH) and cocaine (COC), for example, depend on the ability to increase dopamine ...
Cannabidiol Counteracts Amphetamine-Induced Neuronal and Behavioral Sensitization of the Mesolimbic Dopamine Pathway through a Novel mTOR/p70S6 Kinase Signaling Pathway | Journal of Neuroscience
Schizophrenia-related psychosis is associated with disturbances in mesolimbic dopamine (DA) transmission, characterized by hyperdopaminergic activity in the mesolimbic pathway. Currently, the only clinically effective treatment for schizophrenia involves the use of antipsychotic medications that block DA receptor transmission. However, these medications produce serious side effects leading to poor compliance and treatment outcomes. Emerging evidence points to the involvement of a specific phytochemical component of marijuana called cannabidiol (CBD), which possesses promising therapeutic properties for the treatment of schizophrenia-related psychoses. However, the neuronal and molecular mechanisms through which CBD may exert these effects are entirely unknown. We used amphetamine (AMPH)-induced sensitization and sensorimotor gating in rats, two preclinical procedures relevant to schizophrenia-related psychopathology, combined with in vivo single-unit neuronal electrophysiology recordings in the ventral tegmental area, and molecular analyses to characterize the actions of CBD directly in the nucleus accumbens shell (NASh), a brain region that is the current target of most effective antipsychotics. We demonstrate that Intra-NASh CBD attenuates AMPH-induced sensitization, both in terms of DAergic neuronal activity measured in the ventral tegmental area and psychotomimetic behavioral analyses. We further report that CBD controls downstream phosphorylation of the mTOR/p70S6 kinase signaling pathways directly within the NASh. Our findings demonstrate a novel mechanism for the putative antipsychotic-like properties of CBD in the mesolimbic circuitry. We identify the molecular signaling pathways through which CBD may functionally reduce schizophrenia-like neuropsychopathology. SIGNIFICANCE STATEMENT The cannabis-derived phytochemical, cannabidiol (CBD), has been shown to have pharmacotherapeutic efficacy for the treatment of schizophrenia. However, the mechanisms by which CBD may produce antipsychotic effects are entirely unknown. Using preclinical behavioral procedures combined with molecular analyses and in vivo neuronal electrophysiology, our findings identify a functional role for the nucleus accumbens as a critical brain region whereby CBD can produce effects similar to antipsychotic medications by triggering molecular signaling pathways associated with the effects of classic antipsychotic medications. Specifically, we report that CBD can attenuate both behavioral and dopaminergic neuronal correlates of mesolimbic dopaminergic sensitization, via a direct interaction with mTOR/p70S6 kinase signaling within the mesolimbic pathway.
