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Reumatologia ClinicaThe clinical anatomy of several pain syndromes of the knee is herein discussed. These include the iliotibial tract syndrome, the anserine syndrome, bursitis of the... (Review)
Review
The clinical anatomy of several pain syndromes of the knee is herein discussed. These include the iliotibial tract syndrome, the anserine syndrome, bursitis of the medial collateral ligament, Baker's cyst, popliteus tendon tenosynovitis and bursitis of the deep infrapatellar bursa. These syndromes are reviewed in terms of the structures involved and their role in knee physiology. All of the discussed structures can be identified in their normal state and more so when they are affected by disease. The wealth of information gained by cross examination of the medial, lateral, posterior and anterior aspects of the knee brings to life knowledge acquired at the dissection table, from anatomical drawings and from virtual images.
Topics: Diagnosis, Differential; Humans; Knee Injuries; Knee Joint; Musculoskeletal Diseases; Musculoskeletal Pain; Physical Examination; Syndrome
PubMed: 23219082
DOI: 10.1016/j.reuma.2012.10.002 -
Physiological Reviews Oct 2013Carnosine (β-alanyl-l-histidine) was discovered in 1900 as an abundant non-protein nitrogen-containing compound of meat. The dipeptide is not only found in skeletal... (Review)
Review
Carnosine (β-alanyl-l-histidine) was discovered in 1900 as an abundant non-protein nitrogen-containing compound of meat. The dipeptide is not only found in skeletal muscle, but also in other excitable tissues. Most animals, except humans, also possess a methylated variant of carnosine, either anserine or ophidine/balenine, collectively called the histidine-containing dipeptides. This review aims to decipher the physiological roles of carnosine, based on its biochemical properties. The latter include pH-buffering, metal-ion chelation, and antioxidant capacity as well as the capacity to protect against formation of advanced glycation and lipoxidation end-products. For these reasons, the therapeutic potential of carnosine supplementation has been tested in numerous diseases in which ischemic or oxidative stress are involved. For several pathologies, such as diabetes and its complications, ocular disease, aging, and neurological disorders, promising preclinical and clinical results have been obtained. Also the pathophysiological relevance of serum carnosinase, the enzyme actively degrading carnosine into l-histidine and β-alanine, is discussed. The carnosine system has evolved as a pluripotent solution to a number of homeostatic challenges. l-Histidine, and more specifically its imidazole moiety, appears to be the prime bioactive component, whereas β-alanine is mainly regulating the synthesis of the dipeptide. This paper summarizes a century of scientific exploration on the (patho)physiological role of carnosine and related compounds. However, far more experiments in the fields of physiology and related disciplines (biology, pharmacology, genetics, molecular biology, etc.) are required to gain a full understanding of the function and applications of this intriguing molecule.
Topics: Animals; Brain; Cardiovascular Physiological Phenomena; Carnosine; Dipeptidases; Disease Models, Animal; Female; Humans; Male; Muscle, Skeletal
PubMed: 24137022
DOI: 10.1152/physrev.00039.2012 -
Amino Acids Mar 2020Taurine (a sulfur-containing β-amino acid), creatine (a metabolite of arginine, glycine and methionine), carnosine (a dipeptide; β-alanyl-L-histidine), and... (Review)
Review
Taurine (a sulfur-containing β-amino acid), creatine (a metabolite of arginine, glycine and methionine), carnosine (a dipeptide; β-alanyl-L-histidine), and 4-hydroxyproline (an imino acid; also often referred to as an amino acid) were discovered in cattle, and the discovery of anserine (a methylated product of carnosine; β-alanyl-1-methyl-L-histidine) also originated with cattle. These five nutrients are highly abundant in beef, and have important physiological roles in anti-oxidative and anti-inflammatory reactions, as well as neurological, muscular, retinal, immunological and cardiovascular function. Of particular note, taurine, carnosine, anserine, and creatine are absent from plants, and hydroxyproline is negligible in many plant-source foods. Consumption of 30 g dry beef can fully meet daily physiological needs of the healthy 70-kg adult human for taurine and carnosine, and can also provide large amounts of creatine, anserine and 4-hydroxyproline to improve human nutrition and health, including metabolic, retinal, immunological, muscular, cartilage, neurological, and cardiovascular health. The present review provides the public with the much-needed knowledge of nutritionally and physiologically significant amino acids, dipeptides and creatine in animal-source foods (including beef). Dietary taurine, creatine, carnosine, anserine and 4-hydroxyproline are beneficial for preventing and treating obesity, cardiovascular dysfunction, and ageing-related disorders, as well as inhibiting tumorigenesis, improving skin and bone health, ameliorating neurological abnormalities, and promoting well being in infants, children and adults. Furthermore, these nutrients may promote the immunological defense of humans against infections by bacteria, fungi, parasites, and viruses (including coronavirus) through enhancing the metabolism and functions of monocytes, macrophages, and other cells of the immune system. Red meat (including beef) is a functional food for optimizing human growth, development and health.
Topics: Animals; Anserine; Carnosine; Cattle; Creatine; Humans; Hydroxyproline; Nutritive Value; Red Meat; Taurine
PubMed: 32072297
DOI: 10.1007/s00726-020-02823-6 -
Antioxidants (Basel, Switzerland) Dec 2022Anserine and carnosine have nephroprotective actions; hydrogen sulfide (HS) protects from ischemic tissue damage, and the underlying mechanisms are debated. In view of...
Anserine and carnosine have nephroprotective actions; hydrogen sulfide (HS) protects from ischemic tissue damage, and the underlying mechanisms are debated. In view of their common interaction with HSP70, we studied possible interactions of both dipeptides with HS. HS formation was measured in human proximal tubular epithelial cells (HK-2); three endothelial cell lines (HUVEC, HUAEC, MCEC); and in renal murine tissue of wild-type (WT), carnosinase-1 knockout -KO) and -KO mice. Diabetes was induced by streptozocin. Incubation with carnosine increased HS synthesis capacity in tubular cells, as well as with anserine in all three endothelial cell lines. HS dose-dependently reduced anserine/carnosine degradation rate by serum and recombinant carnosinase-1 (CN1). Endothelial -KO reduced HS formation and abolished the stimulation by anserine and could be restored by transfection. In female -KO mice, kidney HS formation was halved. In -KO mice, kidney anserine concentrations were several-fold and sex-specifically increased. Kidney HS formation capacity was increased 2-3-fold in female mice and correlated with anserine and carnosine concentrations. In diabetic -KO mice, renal anserine and carnosine concentrations as well as HS formation capacity were markedly reduced compared to non-diabetic -KO littermates. Anserine and carnosine induce HS formation in a cell-type and Hsp70-specific manner within a positive feedback loop with CN1.
PubMed: 36670928
DOI: 10.3390/antiox12010066 -
Molecules (Basel, Switzerland) Feb 2014Carnosinases are Xaa-His dipeptidases that play diverse functions throughout all kingdoms of life. Human isoforms of carnosinase (CN1 and CN2) under appropriate... (Review)
Review
Carnosinases are Xaa-His dipeptidases that play diverse functions throughout all kingdoms of life. Human isoforms of carnosinase (CN1 and CN2) under appropriate conditions catalyze the hydrolysis of the dipeptides carnosine (β-alanyl-L-histidine) and homocarnosine (γ-aminobutyryl-L-histidine). Alterations of serum carnosinase (CN1) activity has been associated with several pathological conditions, such as neurological disorders, chronic diseases and cancer. For this reason the use of carnosinase levels as a biomarker in cerebrospinal fluid (CSF) has been questioned. The hydrolysis of imidazole-related dipeptides in prokaryotes and eukaryotes is also catalyzed by aminoacyl-histidine dipeptidases like PepD (EC 3.4.13.3), PepV (EC 3.4.13.19) and anserinase (EC 3.4.13.5). The review deals with the structure and function of this class of enzymes in physiological and pathological conditions. The main substrates of these enzymes, i.e., carnosine, homocarnosine and anserine (β-alanyl-3-methyl-L-histidine) will also be described.
Topics: Carnosine; Dipeptidases; Dipeptides; Humans; Neoplasms; Nervous System Diseases; Protein Conformation; Structure-Activity Relationship; Substrate Specificity
PubMed: 24566305
DOI: 10.3390/molecules19022299