Fenugreek
Dilip Ghosh, Prasad Thakurdesai in Fenugreek, 2022
It is the free amino acid found specifically in selected plants of the Trigonella genus. It comprises nearly up to 80% of the total amino acids (0.015–0.4%) of fenugreek seeds (Hajimehdipoor et al. 2010). It is derived from isoleucine hydroxylation and exists in two isomeric forms, and major fraction constitutes 2S, 3R, 4S while the minor exhibits 2R, 3R, 4S configuration. Optical rotation yields a value of [αD] + 30.5 (c = 1, H2O), [αD] + 31 (c = 1.1, H2O). It is available as white powder or flakes. The melting point is 223.5 °C. The molecular weight is 147.1 as per the mass spectrometric evaluation (Hari and Mohan 2014). Under acidic conditions, the linear form may convert to lactone form. The linear form of isoleucine is biologically active. In S-confirmation, full methylation at carbon-α and carbon-γ hydroxylation are essential for insulinotropic activity (Broca et al. 2000).
Cognitive symptoms related to attention
Aurora Lassaletta, Ruth Clarke in The Invisible Brain Injury, 2019
Personally, I was thrilled whenever doctors in different fields suggested doing a particular test on me that could give an explanation for my fatigue or other effects: “I think you must have terrible anaemia”, “Let’s give you a hormone injection to see how your adrenal gland reacts, and I’m sure that will give us an explanation”. They thought that my symptoms would be reflected in the test results. Normally all the tests came out fine, which I was very happy about, but I would sincerely have liked to have a biochemical explanation for some of my impairments, to seek possible treatment. It also cannot be explained as an emotional thing, an easy conclusion to jump to when tests are shown to be within the normal range. “I’M NOT SAD, I’M TIRED!” has been my cry on many occasions. Because I know perfectly well what it feels like to be sad; I’ve had moments where my mood was really very low. My family and I, now, with time, can tell the difference between the apathy and tiredness of depression and the fatigue of brain injury.
Molecular Mechanisms of Training Effects
Atko Viru in Adaptation in Sports Training, 2017
Addition of valine, glutamine, metionine, phenylalanine or tyrosine to the incubation medium in vitro did not change the rate of protein synthesis in striated muscle tissue. Isoleucine inhibited the rate.75 In skeletal muscle, raised intracellular glutamine concentrations increase protein synthesis and inhibit overall but not myofibrillar protein degradation in vitro.86 When isoleucine and valine were added in combination, the labeled amino acid incorporation was augmented, but to a smaller extent than in administration of leucine alone.76 Branched-chain amino acids (leucine, valine, and isoleucine) stimulated protein synthesis also when they were administered in vivo. This effect was pronounced in the myocardium, diaphragm, and soleus muscle,77 i.e., in muscles possessing a high oxidation potential. An increased perfusate concentration of branched-chain amino acids increased protein synthesis rate in the skeletal muscles of young rats, but not in fasted adult rats.87
Intakes of Total and Branched-Chain Essential Amino Acids are Positively Associated with Handgrip Strength in African American and White Urban Younger and Older Adults
Published in Journal of Nutrition in Gerontology and Geriatrics, 2022
Marie Fanelli Kuczmarski, May A. Beydoun, Alan B. Zonderman, Michele K. Evans
The contribution of each EAA from 8 food groups for the overall sample (presenting in descending order), as well as by African American and White participants, is provided in Table 3. Of these eight groups, four groups would be considered high-quality protein sources, namely meats/poultry, dairy, eggs, and fish. The top two food groups which contributed EAAs to the HANDLS study participants were meats/poultry and mixed dishes. Meats/poultry were the top contributing food group for histidine, isoleucine, lysine, methionine/cysteine, threonine, and valine. Mixed dishes, consisting of eight subgroups: combinations of meats, bean/vegetable, and grain-based items, Asian, Mexican, soups, pizza or singled-coded sandwiches, ranked first for leucine, phenylalanine, and tryptophan. These two groups contributed roughly half of the daily intake of the EAAs. The high-quality protein groups that contributed the smallest quantities of EAAs daily were eggs and fish. For the HANDLS study total sample, the plant-based protein group contributed approximately 2% of each of the EAAs, ranking last (Table 3).
Toxicity of the herbicides used on herbicide-tolerant crops, and societal consequences of their use in France
Published in Drug and Chemical Toxicology, 2022
The molecules of the imidazolinone (IMI) and sulfonylurea (SUL) chemical families are used as herbicides. Their primary site of action is the enzyme acetolactate synthase (ALS), also known as acetohydroxyacid synthase (AHAS), of which they are inhibitors (the molecules of the triazolopyrimidine sulfonamide, pyrimidinylthiobenzoate, and sulfonylamino-carbonyltriazolinone chemical families are also inhibitors of ALS: Mallory-Smith and Retzinger 2003). This enzyme is involved in the synthesis of the amino acids valine, leucine, and isoleucine (Zhou et al. 2007). The inhibition of this enzyme by this type of herbicides consequently causes a toxic accumulation of α-ketoglutarate along with a deficit of protein synthesis in the polluted plants, and in the long term the inability to grow or death. Bacteria, fungi, and yeasts also have this enzyme, making all of the species represented by these branches of life potential targets (Boldt and Jacobsen 1998; Duggleby et al.2003, Desai et al.2009; Rachedi et al.2018). Aquatic plants such as the duckweed Lemna minor are also affected by these herbicides (Peterson et al. 1994).
The role of the Notch pathway in the pathogenesis of systemic sclerosis: clinical implications
Published in Expert Review of Clinical Immunology, 2021
Filipe Seguro Paula, José Delgado Alves
The first in-human study using an anti-Notch mAb was with brontictuzumab [90], but again the gastrointestinal side effects were considerable, especially with the chronic use. Several others have been developed, mainly targeting the ligand-binding extracellular domains of the Notch receptors. It is noteworthy that one of them, by targeting specifically Notch1, averted the gastrointestinal toxicity in a preclinical study, supposedly by leaving the Notch2 signaling intact [89]. The same logic applies to a mAb against Notch-3, which would not produce goblet cell hyperplasia and diarrhea, as those effects are dependent on Notch-1/Notch-2 signaling. However, gastrointestinal side-effects still existed, including nausea and abdominal pain in up to 25% of participants of a phase I clinical trial [91], despite being reportedly well tolerated. Notch-3 inhibition could be helpful in patients with SSc as it is one of the two most important receptors in myofibroblasts and vascular smooth muscle cells.
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