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help turn fat into energy

Carnitine, Esters: Explanation of the Biomarker in a Carnitine and Acylcarnitine Panel Carnitine esters are a group of compounds formed when carnitine binds to fatty acids. These esters play a critical role in the transport of long-chain fatty acids into the mitochondria, where they are used for energy production. This process is essential for cellular metabolism, particularly in tissues with high energy demands, such as muscles and the heart. In a Carnitine and Acylcarnitine panel, the measurement of carnitine esters (expressed in µmol/L) provides valuable insight into the body's ability to metabolize fatty acids and produce energy efficiently. Elevated or decreased levels of carnitine esters can indicate underlying metabolic or mitochondrial disorders, and abnormalities may suggest issues with fatty acid metabolism, such as primary carnitine deficiency or other metabolic conditions. Reference Range Normal Range: 4-13 µmol/L Interpretation: Values outside the reference range may indicate metabolic irregularities. Lower levels could suggest impaired fatty acid transport or mitochondrial dysfunction, while higher levels might be linked to conditions affecting fatty acid metabolism or a disturbance in carnitine uptake. Clinical Relevance: Low Levels: Carnitine ester deficiency can result from genetic disorders like primary carnitine deficiency or secondary deficiencies due to poor dietary intake, certain medications, or malabsorption conditions. This can lead to muscle weakness, fatigue, and in severe cases, heart and liver issues. High Levels: Elevated carnitine esters might indicate conditions such as disorders of fatty acid oxidation or an excess of free carnitine in the system. It may also be observed in cases of kidney dysfunction, where carnitine is not properly metabolized or excreted. Measuring carnitine esters alongside other biomarkers in the panel can help clinicians diagnose metabolic disorders and tailor appropriate treatments to manage any identified conditions. If you notice abnormal results for carnitine esters, consulting with a healthcare provider is crucial for further investigation and management.

Serum carnitine analysis is useful in the diagnosis and monitoring of patients with carnitine deficiency (either primary or secondary).

Carnitine is a compound in the body that helps your body digest fats for energy. A carnitine deficiency is related to a number of different medical problems. A carnitine total and free plasma test is a blood test that measures the amount of carnitine in the blood. It examines that amount of usable, or free, carnitine and compares it with the total amount of carnitine. The analysis of carnitines is indicated in people who exhibit the following: - failure to thrive, - hypotonia, - chronic muscle weakness, - cardiomyopathy, - intermittent episodes of weakness and encephalopathy, - renal Fanconi's syndrome, - hypoglycemic episodes, - metabolic acidosis, - or hypoketotic dicarboxylic acidurias. ------------------ Reference Ranges: Carnitine is a quaternary, water-soluble ammonia compound biosynthesized from lysine and arginine. It serves as a mechanism for transport of long-chain fatty acids from the cytoplasm across the inner mitochondrial membrane and into the mitochondrial matrix, the site of b-oxidation of fatty acids for energy generation. The reference range of carnitine depends on the laboratory being used; Reference Range of Carnitine at a Single Laboratory Age Range Serum Free Carnitine (µmol/L) Serum Total Carnitine (µmol/L) Neonate 26-76 35-102 Child 41.4±10.4* 56.2±11.4* Adolescent female 39.3±8.1* 53.2±8.9* Adolescent male 39.6±9.3* 53.5±10.5* Adult female 19.3-53.9** 28.1-66.4** Adult male 38.8-69.5 44.2-79.3 *Mean ± standard deviation (SD) **95% confidence interval (CI) Quest Laboratories reports the reference range of total carnitine as follows: Men: 30-70 μmol/L Women: 25-58 μmol/L Male children (age ≤17 years): 32-62 μmol/L Female children (age ≤17 years): 28-59 μmol/L Quest Laboratories reports the reference range of free carnitine as follows: Men: 23-59 μmol/L Women: 19-48 μmol/L Male children (age ≤17 years): 25-54 μmol/L Female children (age ≤17 years): 19-51 μmol/L The University of California San Francisco Laboratory reports the normal values of free and total carnitine in adults as 18-69 μmol/L and 20-71 μmol/L, respectively. Chace et al (2003) examined free and total carnitine levels in newborns. The reference ranges depended both on technique used (radioenzyme vs tandem mass spectroscopy) and the sample type (whole blood vs serum). Variations in the ratio of free to total carnitine may also be important; typically, normal is reported as 0.1-0.4. References: Minkler PE, Stoll MS, Ingalls ST, Kerner J, Hoppel CL. Validated Method for the Quantification of Free and Total Carnitine, Butyrobetaine, and Acylcarnitines in Biological Samples. Anal Chem. 2015 Sep 1. 87 (17):8994-9001. [QxMD MEDLINE Link]. Belay B, Esteban-Cruciani N, Walsh CA, Kaskel FJ. The use of levo-carnitine in children with renal disease: a review and a call for future studies. Pediatr Nephrol. 2006 Mar. 21(3):308-17. [QxMD MEDLINE Link]. Quest Diagnostics. Available at http://www.questdiagnostics.com/testcenter/%20BUOrderInfo.action?tc=5800&labCode=AMD. Chace DH, Pons R, Chiriboga CA, et al. Neonatal blood carnitine concentrations: normative data by electrospray tandem mass spectometry. Pediatr Res. 2003 May. 53(5):823-9. [QxMD MEDLINE Link]. Stanley CA. Carnitine deficiency disorders in children. Ann N Y Acad Sci. 2004 Nov. 1033:42-51. [QxMD MEDLINE Link]. Reuter SE, Evans AM. Carnitine and acylcarnitines: pharmacokinetic, pharmacological and clinical aspects. Clin Pharmacokinet. 2012 Sep 1. 51(9):553-72. [QxMD MEDLINE Link]. Longo N, Amat di San Filippo C, Pasquali M. Disorders of carnitine transport and the carnitine cycle. Am J Med Genet C Semin Med Genet. 2006 May 15. 142C(2):77-85. [QxMD MEDLINE Link]. [Full Text]. Dahash BA, Sankararaman S. Carnitine Deficiency. StatPearls. 2022 Jan. [QxMD MEDLINE Link]. [Full Text]. Santra S, Hendriksz C. How to use acylcarnitine profiles to help diagnose inborn errors of metabolism. Arch Dis Child Educ Pract Ed. 2010 Oct. 95(5):151-6. [QxMD MEDLINE Link]. Scaglia F. Carnitine Deficiency. Medscape Drugs & Diseases. Updated 2019 Dec 13. [Full Text]. Magoulas PL, El-Hattab AW. Systemic primary carnitine deficiency: an overview of clinical manifestations, diagnosis, and management. Orphanet J Rare Dis. 2012 Sep 18. 7:68. [QxMD MEDLINE Link]. [Full Text]. Tein I. Metabolic myopathies. Swaiman KF, Ashwal S, Ferriero DM. Swaiman’s Pediatric Neurology Principles and Practice. 5th ed. Schor NF: Elsevier Sanders; 2012. 1627-40. Crefcoeur LL, Visser G, Ferdinandusse S, Wijburg FA, Langeveld M, Sjouke B. Clinical characteristics of primary carnitine deficiency: A structured review using a case-by-case approach. J Inherit Metab Dis. 2022 May. 45 (3):386-405. [QxMD MEDLINE Link]. [Full Text]. Berardo A, DiMauro S, Hirano M. A diagnostic algorithm for metabolic myopathies. Curr Neurol Neurosci Rep. 2010 Mar. 10(2):118-26. [QxMD MEDLINE Link]. [Full Text]. Bernardini I, Rizzo WB, Dalakas M, Bernar J, Gahl WA. Plasma and muscle free carnitine deficiency due to renal Fanconi syndrome. J Clin Invest. 1985 Apr. 75(4):1124-30. [QxMD MEDLINE Link]. [Full Text]. Gahl WA, Bernardini I, Dalakas M, et al. Oral carnitine therapy in children with cystinosis and renal Fanconi syndrome. J Clin Invest. 1988 Feb. 81(2):549-60. [QxMD MEDLINE Link]. [Full Text]. Determination of Free and Total Carnitine and Choline in Infant Formulas and Adult Nutritional Products by UHPLC-MS/MS: Single-Laboratory Validation, First Action 2014.04. J AOAC Int. 2015 Jun 24. [QxMD MEDLINE Link]. El-Hattab AW. Systemic Primary Carnitine Deficiency. 1993. [QxMD MEDLINE Link]. Rinaldo P, Cowan TM, Matern D. Acylcarnitine profile analysis. Genet Med. 2008 Feb. 10(2):151-6. [QxMD MEDLINE Link]. Dietzen DJ, Rinaldo P, Whitley RJ, et al. National academy of clinical biochemistry laboratory medicine practice guidelines: follow-up testing for metabolic disease identified by expanded newborn screening using tandem mass spectrometry; executive summary. Clin Chem. 2009 Sep. 55(9):1615-26. [QxMD MEDLINE Link]. Johns Hopkins University Clinical Lab. National Newborn Screening Status Report 2012. Stanley CA. Carnitine disorders. Adv Pediatr. 1995. 42:209-42. [QxMD MEDLINE Link]. Mamedov I, Zolkina I, Nikolaeva E, Glagovsky P, Sukhorukov V. Carnitine insufficiency in children with inborn errors of metabolism: prevalence and treatment efficacy. J Pediatr Endocrinol Metab. 2015 Jul 18. [QxMD MEDLINE Link]. Sgambat K, Moudgil A. Carnitine deficiency in children receiving continuous renal replacement therapy. Hemodial Int. 2015 Aug 11. [QxMD MEDLINE Link].

Dietary Peptide Related Markers

Carnosine is generally very low and increases proportionally after meat intake. Urine levels peak after ~5 hours and are completely excreted within 20–25 hours. Urine carnosine increased with albuminuria in patients with diabetes. People with eGFR < 30 ml/mi had higher urine-carnosine excretion rates compared to eGFR (> 90 ml).

Dietary Peptide Related Markers

A dietary peptide

Dietary Peptide Related Markers

Carnosine is a dietary peptide related marker that consists of histidine and beta-alanine. Carnosine is an incompletely digested peptide that is derived primarily from beef and pork.

Dietary Peptide Related Markers

Carnosine is a dipeptide molecule composed of the amino acids beta-alanine and histidine, and it is found primarily in muscle and brain tissues. When measured in urine, carnosine levels can provide valuable insights into an individual's muscle metabolism and overall health. Elevated levels of carnosine in the urine may indicate increased muscle breakdown or high dietary intake of carnosine-rich foods, such as meat and fish. Conversely, low levels could suggest issues with muscle synthesis or insufficient dietary intake. Carnosine is known for its antioxidant properties and its role in buffering lactic acid in muscles during intense physical activity, which helps reduce muscle fatigue and improve performance. By analyzing the carnosine levels in urine, healthcare providers can gain insights into a person's nutritional status, muscle health, and potential metabolic issues, allowing for more personalized and effective health and nutrition interventions.

The Carotene marker in a blood panel is a significant indicator of dietary intake and absorption of carotenoids, primarily beta-carotene, a precursor to Vitamin A. Beta-carotene, found abundantly in fruits and vegetables like carrots, sweet potatoes, and leafy greens, is renowned for its antioxidant properties and its role in maintaining healthy vision, skin, and immune function. Elevated levels of the Carotene marker generally reflect a diet rich in these nutrients, which is beneficial for overall health. However, excessively high levels, though rare and usually harmless, can lead to carotenemia, a condition characterized by yellowing of the skin, especially on the palms and soles. This condition is usually dietary and reversible. On the other hand, low levels of carotene in the blood may indicate poor dietary intake of carotenoid-rich foods or issues with nutrient absorption. Monitoring carotene levels can be particularly important for individuals with dietary restrictions or specific medical conditions that affect nutrient absorption. Healthcare professionals use this marker to assess dietary habits, guide nutritional counseling, and address potential health concerns related to Vitamin A deficiency or excess. Understanding the Carotene marker's role is crucial, as it not only reflects dietary intake but also provides insights into the body's ability to process and utilize essential nutrients, underscoring the importance of a balanced diet for optimal health.

Carotene, Beta is a key biomarker often measured in clinical labs to assess nutritional status, particularly vitamin A levels. Beta-carotene is a precursor to vitamin A (retinol) and is one of the most common carotenoids found in plants, especially in colorful fruits and vegetables like carrots, sweet potatoes, and spinach. Key Points About Beta-Carotene: → Function: Beta-carotene is converted into vitamin A in the liver. Vitamin A plays an essential role in vision, immune function, and skin health. It also has antioxidant properties, which help neutralize free radicals and protect cells from oxidative damage. → Clinical Relevance: Measuring beta-carotene levels can provide insight into a person’s vitamin A status, especially in cases of malnutrition, dietary insufficiency, or fat malabsorption syndromes, which can prevent the absorption of fat-soluble vitamins like A, D, E, and K. → Deficiency: Low levels of beta-carotene may indicate inadequate intake of vitamin A precursors or issues with fat absorption. Vitamin A deficiency can lead to conditions like night blindness, dry skin, and a weakened immune response. → Excess: While beta-carotene itself is generally considered safe in high doses, very high intake can cause carotenemia, a harmless condition where the skin turns yellowish-orange, particularly on the palms and soles. Excessive vitamin A, however, (from supplements or liver, not beta-carotene) can lead to toxicity, causing symptoms such as nausea, dizziness, and liver damage. → Lab Measurement: In clinical labs, beta-carotene is typically measured through blood tests. Normal serum concentrations range from approximately 0.3 to 2.5 µmol/L, though this may vary depending on the population and lab reference standards. → Factors Influencing Levels: Dietary intake is the main factor determining beta-carotene levels, but several factors can influence absorption and conversion, including liver function, thyroid activity, and the presence of other nutrients like zinc and protein.