TRβ/thyroid hormone receptor

The TRbeta selective agonist KB-141 induces 5-10% increases in metabolic rate and lowering of plasma cholesterol levels without tachycardia in lean rats, unlike the major active thyroid hormone, T3. In the current study, we determined whether KB-141 promotes weight loss in obese animals and whether it exhibits anti-diabetogenic effects. Body weight, adiposity (DEXA), and lipid levels were examined following p.o. administration of KB-141 to obese Zucker fa/fa rats at 0.00547-0.547 mg/kg/day for 21 days, and in ob/ob mice at 0.5mg/kg/day KB-141 for 7 days. In rats, KB-141 reduced body weight by 6 and 8%, respectively, at 0.167 and 0.0547 mg/kg/day without tachycardia and adiposity was reduced at 0.167 mg/kg/day (5-6%). In ob/ob mice, KB-141 lowered serum cholesterol (35%), triacylglycerols (35%) and both serum and hepatic free fatty acids (18-20%) without tachycardia. Treatment of ob/ob mice with KB-141 (0.0547 or 0.328 mg/kg/day over 2 weeks) improved glucose tolerance and insulin sensitivity in a dose-dependent manner with no effect on heart rate. Thus, KB-141 elicits anti-obesity, lipid lowering and anti-diabetic effects without tachycardia suggesting that selective TRbeta activation may be useful strategy to attenuate features of the metabolic syndrome.[2]
Thus, it should perhaps not have come as a surprise that TR activation by GC-1 and KB2115 could aggravate the hyperglycemia of ob/ob mice. However, we were perplexed by other studies in our group that seemed to indicate that GC-1 could significantly improve glycemic control in multiple mouse models, including ob/ob mice (data not shown). Furthermore, an earlier study involving an agonist closely related to GC-1 (KB141) found that the compound had strong anti-diabetic actions in ob/ob mice [17]. Analysis of the available data led us to suspect that dosage and duration of treatment may be responsible for the seemingly contradictory observations relating TR activation to glycemic control. In order to explore the basis for these discrepancies, we treated mice with either KB2115 or varying doses of GC-1 (referred to here as low-, medium-, and high-dose GC-1) and monitored changes in ad libitum (fed) blood glucose levels during the course of treatment[1].

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In rodent models of insulin resistance, the TR agonist KB141 was shown to elicit striking improvements in glycemic control and insulin sensitivity when administered to ob/ob mice[1].

Several metabolic products that derive from L-thyroxine (T4) and 3,3'5-L-triiodothyronine (T3), the main thyroid hormones secreted by the thyroid gland, possess biologic activities. Among these metabolites or derivatives showing physiological actions some have received greater attention: diiodothyronines, iodothyronamines, acetic acid analogues. It is known that increased thyroid hormone (T3 and T4) levels can improve serum lipid profiles and reduce body fat. These positive effects are, however, counterbalanced by adverse effects on the heart, muscle and bone, limiting their use. In addition to the naturally occurring metabolites, thyroid hormone analogues have been developed that either have selective effects on specific tissues or bind selectively to thyroid hormone receptor (TR) isoform. Among these GC-1, KB141, KB2115, and DITPA were deeply investigated and displayed promising therapeutic results in the potential treatment of conditions such as dyslipidemias and obesity. In this review, we summarize the current knowledge of metabolites and analogues of T4 and T3 with reference to their possible clinical application in the treatment of human diseases[1].

[1]. Martagón AJ, et al. The amelioration of hepatic steatosis by thyroid hormone receptor agonists is insufficient to restore insulin sensitivity in ob/ob mice. PLoS One. 2015 Apr 7;10(4):e0122987.
[2]. Anti-obesity, anti-diabetic, and lipid lowering effects of the thyroid receptor beta subtype selective agonist KB-141. J Steroid Biochem Mol Biol . 2008 Sep;111(3-5):262-7.

A cholesterol-lowering drug.

C17H16CL2O4

355.21

354.042

C, 57.48; H, 4.54; Cl, 19.96; O, 18.02

219691-94-8

9863447

Typically exists as solid at room temperature

1.4±0.1 g/cm3

464.7±45.0 °C at 760 mmHg

234.9±28.7 °C

0.0±1.2 mmHg at 25°C

1.606

4.75

2

4

5

23

392

0

ClC1C=C(CC(=O)O)C=C(C=1OC1=CC=C(C(=C1)C(C)C)O)Cl

OZYQIQVPUZANTM-UHFFFAOYSA-N

InChI=1S/C17H16Cl2O4/c1-9(2)12-8-11(3-4-15(12)20)23-17-13(18)5-10(6-14(17)19)7-16(21)22/h3-6,8-9,20H,7H2,1-2H3,(H,21,22)

2-[3,5-dichloro-4-(4-hydroxy-3-propan-2-ylphenoxy)phenyl]acetic acid

KB141; KB 141; KB-141; 219691-94-8; Kb 141; {3,5-Dichloro-4-[4-Hydroxy-3-(Propan-2-Yl)phenoxy]phenyl}acetic Acid; 2-[3,5-dichloro-4-(4-hydroxy-3-propan-2-ylphenoxy)phenyl]acetic acid; M5P363AFVC; CHEMBL41036; IH-5; KB-141

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)