Scientific Name(s): 2 alpha-hydroxy ursolic acid
Common Name(s): Corosolic acid, Glucosol
Corosolic acid is found in numerous plant species, including L. speciosa L., Tiarella polyphylla D. Don, Datisca cannabina L., Eriobotrya japonica (Thunb.) Lindl., and Perilla frutescens (L.) Britton.
Corosolic acid has numerous biological properties including antidiabetic, anti-inflammatory, antiproliferative, and protein kinase C inhibition activity.1, 2 It is found in numerous plants species, particularly L. speciosa.3 Most medical research focuses on the compound's efficacy in diabetes. Glucosol (or GlucoFit) is a commercially available product primarily marketed in Japan and the United States as a dietary supplement for weight loss and blood sugar balance.1 Corosolic acid is found in numerous cosmetic products, including creams, lotions, hair tonics, as well as in hypoglycemic health foods.3, 4, 5
Corosolic acid is a naturally occurring pentacyclic triterpene also known as 2 alpha-hydroxy ursolic acid.6, 7 Chemical analyses focus on the study of corosolic acid and its derivatives as inhibitors of glycogen phosphorylases for potential development of antidiabetic agents.1, 6 There is documented commercial interest in improving the chemical production of corosolic acid and its esters.8, 9
Uses and Pharmacology
In vitro data
Corosolic acid has cytotoxic activity against several human cancer cell lines. The compound antagonized morphological modification of K-562 leukemic cells. The mechanism of action may be associated with suppression of protein kinase C activity.10 In addition, cytotoxic activity has been documented against human cancer cell lines HL-60 (leukemia carcinoma), MCF-7 (breast carcinoma), and Hep-G2 (hepatic carcinoma).11
In a 2-stage Berenblum experiment on mouse skin papillomas, the inhibitory effect of corosolic acid was comparable or equivalent to beta-carotene, rosmarinic acid, and alpha-linolenic acid.12
Corosolic acid may improve the insulin pathway. The action of insulin is mediated by tyrosine phosphorylation and initiated by the binding of insulin to the insulin receptor. Corosolic acid may act as an insulin sensitizer, enhancing insulin receptor B phosphorylation indirectly by inhibiting certain nonreceptor protein tyrosine phosphatases.13 Corosolic acid may also enhance GLUT4 glucose transporter processing of glucose uptake into muscle cells.14 Another study reported that corosolic acid inhibited gluconeogenesis by increasing the production of the gluconeogenic intermediate fructose-2,6-bisphosphate in isolated hepatocytes. Corosolic acid may promote glycolysis.15, 16
Numerous animal experiments document the effect of corosolic acid on blood glucose. One study in rats found that 1% corosolic acid reduced blood glucose levels at 90 minutes after oral administration.17 Treatment with corosolic acid lowered plasma insulin levels and reduced the blood glucose levels in KK-Ay mice 2 weeks after a single oral dose of 2 mg/kg. Blood glucose in KK-Ay mice treated with corosolic acid decreased in an insulin tolerance test.18 Another experiment showed similar inhibitory action against increasing blood glucose levels.19 Increasing the concentration of corosolic acid may lead to enhanced glucose uptake activity.20 Corosolic acid induced muscle GLUT4 translocation from low-density microsomal membrane to plasma membrane in genetically-induced type 2 diabetic mice.14, 16
In a small randomized clinical trial, 10 patients with type 2 diabetes were treated with an extract from the leaves of L. speciosa standardized to 1% corosolic acid (Glucosol ). Patients receiving Glucosol 32 or 48 mg daily for 2 weeks demonstrated a significant reduction in blood glucose levels. The softgel capsule formulation resulted in a 30% decrease, compared with 20% decrease in blood glucose levels in patients receiving the dry-powder, hard-gelatin capsule formulation. The softgel formulation has better bioavailability, and the active lipophilic triterpene ingredient is better absorbed in an oil-based, soft-gelatin capsule formulation.21
In a study completed in Japan with 31 patients, corosolic acid lowered postchallenge plasma glucose levels.22
Other pharmacologic activity
Corosolic acid enhanced the activity of treatment with tobramycin against Pseudomonas aeruginosa in a biofilm inhibition assay.23
Activity against the classical pathway of the complement system is documented for corosolic acid.24
In an animal model on metabolic syndrome, corosolic acid had antihypertensive, lipid-lowering, antioxidant, and anti-inflammatory effects on rats.25 In a similar study, corosolic acid reduced blood pressure and serum-free fatty acid levels in rats.26
There is in vitro evidence for corosolic acid inhibiting protein tyrosine phosphatase 1B; inhibition of this phosphatase is proposed as a therapy for obesity.27 Corosolic acid is also a pancreatic lipase inhibitor, the main enzyme for lipid absorption.28 In a mouse study, corosolic acid acted as a peroxisome proliferator-activated receptor alpha agonist, regulating lipid metabolism and increasing fatty acid beta-oxidation in the liver.29
Numerous commercial formulations are available, including tablets, capsules, hypoglycemic food products, and cosmetics. Most formulations are available in capsule form containing 18% corosolic acid extracted from L. speciosa. The manufacturer suggested dosage is 1 softgel by mouth 30 minutes before morning and evening meals. Softgel products are marketed for noninsulin dependent type 2 diabetic patients.30, 31, 32
Pregnancy / Lactation
Avoid use. Information regarding safety and efficacy in pregnancy and lactation is lacking.
Counsel patients with diabetes or those taking diabetic medications about the potential additive effects if they are self-medicating with any corosolic oral dietary supplement.
Avoid use with hypersensitivity to any source plants for corosolic acid. Because the product may be derived from several plant species, there is a potential for skin rashes.
A case of severe acute lactic acidosis was attributed to the likely accumulation of corosolic acid in a patient with type 2 diabetes mellitus, gouty arthritis, and stage 3a chronic kidney disease with non-steroidal anti-inflammatory drug (NSAID)-induced acute renal impairment. The patient had been taking corosolic acid daily for 1 month. One week prior to admission, acute NSAID-induced renal hypoperfusion was thought to have occurred after the patient self-medicated with diclofenac for joint pains, which led to a subsequent accumulation of corosolic acid. Corosolic acid has been shown to inhibit gluconeogenesis and enhance glycolysis.33
A single oral dose toxicity study in rats administered Glucosol 5 g/kg showed no marked pathological findings.34
This information relates to an herbal, vitamin, mineral or other dietary supplement. This product has not been reviewed by the FDA to determine whether it is safe or effective and is not subject to the quality standards and safety information collection standards that are applicable to most prescription drugs. This information should not be used to decide whether or not to take this product. This information does not endorse this product as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this product. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. This information is not specific medical advice and does not replace information you receive from your health care provider. You should talk with your health care provider for complete information about the risks and benefits of using this product.
This product may adversely interact with certain health and medical conditions, other prescription and over-the-counter drugs, foods, or other dietary supplements. This product may be unsafe when used before surgery or other medical procedures. It is important to fully inform your doctor about the herbal, vitamins, mineral or any other supplements you are taking before any kind of surgery or medical procedure. With the exception of certain products that are generally recognized as safe in normal quantities, including use of folic acid and prenatal vitamins during pregnancy, this product has not been sufficiently studied to determine whether it is safe to use during pregnancy or nursing or by persons younger than 2 years of age.
Copyright © 2018 Wolters Kluwer Health
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.