ATP-sensitive K+ channel (KATP)

Glibenclamide (brown adipocytes; 10 μM; 1 day) has no effect on adipocyte differentiation. Glibenclamide (Ucp1-2A-GFP brown adipocyte) dramatically increases UCP1 expression. Glibenclamide directly binds to and inhibits the SUR1 subunit of ATP-dependent potassium channels (KATP), consequently boosting insulin production from pancreatic beta cells [2]. Glibenclamide interferes with mitochondrial bioenergetics by allowing Cl- to enter the inner mitochondrial membrane and boosting Cl-/K+ co-transport in the mitochondrial network [4]. Glibenclamide-induced autophagy limits its beneficial effect on β-cell insulin secretion [5].

Glibenclamide (2 mg/kg; po) quickly lowers blood glucose levels and enhances the release of insulin [2]. Body weight and body composition do not significantly alter when using glibeenclamide (50 μg/kg; po) [2].

Glibenclamide is well known to interact with the sulphonylurea receptor (SUR) and has been shown more recently to inhibit the cystic fibrosis transmembrane conductance regulator protein (CFTR), both proteins that are members of the ABC [adenosine 5'-triphosphate (ATP)-binding cassette] transporters. The effect of glibenclamide and two synthetic sulphonylcyanoguanidine derivatives (dubbed BM-208 and BM-223) was examined on P-glycoprotein, the major ABC transporter responsible for multidrug resistance (MDR) in cancer cells. To this end, we employed different cell lines that do or do not express P-glycoprotein, as confirmed by Western blotting: first, a tumour cell line (VBL600) selected from a human T-cell line (CEM) derived from an acute leukaemia; second, an epithelial cell line derived from a rat colonic adenocarcinoma (CC531(mdr+)) and finally, a non tumour epithelial cell line derived from the proximal tubule of the opossum kidney (OK). Glibenclamide and the two related derivatives inhibited P-glycoprotein because firstly, they acutely increased [3H]colchicine accumulation in P-glycoprotein-expressing cell lines only; secondly BM-223 reversed the MDR phenomenon, quite similarly to verapamil, by enhancing the cytotoxicity of colchicine, taxol and vinblastine and thirdly, BM-208 and BM-223 blocked the photoaffinity-labelling of P-glycoprotein by [3H]azidopine. Furthermore, glibenclamide is itself a substrate for P-glycoprotein, since the cellular accumulation of [3H]glibenclamide was low and substantially increased by addition of P-glycoprotein substrates (e. g., vinblastine and cyclosporine) only in the P-glycoprotein-expressing cell lines. We conclude that glibenclamide and two sulphonylcyanoguanidine derivatives inhibit P-glycoprotein and that sulphonylurea drugs would appear to be general inhibitors of ABC transporters, suggesting an interaction with some conserved motif.[3]

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The interference of glibenclamide, an antidiabetic sulfonylurea, with mitochondrial bioenergetics was assessed on mitochondrial ion fluxes (H+, K+, and Cl-) by passive osmotic swelling of rat liver mitochondria in K-acetate, KNO3, and KCl media, by O2 consumption, and by mitochondrial transmembrane potential (Deltapsi). Glibenclamide did not permeabilize the inner mitochondrial membrane to H+, but induced permeabilization to Cl- by opening the inner mitochondrial anion channel (IMAC). Cl- influx induced by glibenclamide facilitates K+ entry into mitochondria, thus promoting a net Cl-/K+ cotransport, Deltapsi dissipation, and stimulation of state 4 respiration rate. It was concluded that glibenclamide interferes with mitochondrial bioenergetics of rat liver by permeabilizing the inner mitochondrial membrane to Cl- and promoting a net Cl-/K+ cotransport inside mitochondria, without significant changes on membrane permeabilization to H+[4].

Diabetes is a metabolic disease, partly due to hypoinsulinism, which affects ∼8% of the world's adult population. Glibenclamide is known to promote insulin secretion by targeting β cells. Autophagy as a self-protective mechanism of cells has been widely studied and has particular physiological effects in different tissues or cells. However, the interaction between autophagy and glibenclamide is unclear. In this study, we investigated the role of autophagy in glibenclamide-induced insulin secretion in pancreatic β cells. Herein, we showed that glibenclamide promoted insulin release and further activated autophagy through the adenosine 5'-monophosphate (AMP) activated protein kinase (AMPK) pathway in MIN-6 cells. Inhibition of autophagy with autophagy inhibitor 3-methyladenine (3-MA) potentiated the secretory function of glibenclamide further. These results suggest that glibenclamide-induced autophagy plays an inhibitory role in promoting insulin secretion by activating the AMPK pathway instead of altering the mammalian target of rapamycin (mTOR)[5].

Animal/Disease Models: Mice[2]
Doses: 2 mg/kg
Route of Administration: Po
Experimental Results: Increased of insulin release and rapid drop of blood glucose level.

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Identification of safe and effective compounds to increase or activate UCP1 expression in brown or white adipocytes remains a potent therapeutic strategy to combat obesity. Here we reported that, glyburide, one of the FDA-approved drugs currently used to treat type 2 diabetes, can significantly enhance UCP1 expression in both brown and white adipocytes. Glyburide-fed mice exhibited a clear resistance to high-fat diet-induced obesity, reduced blood triglyceride level, and increased UCP1 expression in brown adipose tissue. Moreover, in situ injection of glyburide to inguinal white adipose tissue remarkably enhanced UCP1 expression and increased thermogenesis. Further mechanistic studies indicated that the glyburide effect in UCP1 expression in adipocytes was KATP channel independent but may involve the regulation of the Ca2+-Calcineurin-NFAT signal pathway. Overall, our findings revealed the significant effects of glyburide in regulating UCP1 expression and thermogenesis in adipocytes, which can be potentially repurposed to treat obesity.[2]

Absorption, Distribution and Excretion
Elderly patients taking glyburide reached a Cmax of 211-315ng/mL with a Tmax of 0.9-1.0h, while younger patients reached a Cmax of 144-302ng/mL with a Tmax of 1.3-3.0h. Patients taking glyburide have and AUC of 348ng*h/mL.
Unlike other sulfonylureas, glyburide is 50% excreted in the urine and 50% in the feces. Glyburide is mainly excreted as the metabolite 4-trans-hydroxyglyburide.
Elderly patients have a volume of distribution of 19.3-52.6L, while younger patients have a volume of distribution of 21.5-49.3L.
Elderly patients have a clearance of 2.70-3.55L/h, while younger patients have a clearance of 2.47-4.11L/h.

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Metabolism / Metabolites
Glyburide is metabolized mainly by CYP3A4, followed by CYP2C9, CYP2C19, CYP3A7, and CYP3A5. These enzymes metabolize glyburide to 4-trans-hydroxycyclohexyl glyburide (M1), 4-cis-hydroxycyclohexyl glyburide (M2a), 3-cis-hydroxycyclohexyl glyburide (M2b), 3-trans-hydroxycyclohexyl glyburide (M3), 2-trans-hydroxycyclohexyl glyburide (M4), and ethylhydroxycyclohexyl glyburide (M5). The M1 and M2b metabolites are considered active, along with the parent molecule.
Glyburide has known human metabolites that include 3-cis-Hydroxycyclohexyl glyburide, 3-trans-Hydroxycyclohexyl glyburide, 2-trans-hydroxycyclohexyl glyburide, and 4-cis-hydroxycyclohexyl glyburide.

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Biological Half-Life
Elderly patients have a terminal elimination half life of 4.0-13.4h, while younger patients have a terminal elimination half life of 4.0-13.9h.

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Limited data indicate that the levels of glyburide in milk are negligible. Monitor breastfed infants for signs of hypoglycemia such as jitteriness, excessive sleepiness, poor feeding, seizures cyanosis, apnea, or hypothermia. If there is concern, monitoring of the breastfed infant's blood glucose is advisable during maternal therapy with hypoglycemic agents.
◉ Effects in Breastfed Infants
The blood glucose level was normal in one breastfed infant whose mothers was taking oral glyburide 5 mg daily.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
Glyburide is 99.9% bound to protein in plasma with >98% accounted for by binding to serum albumin.

[1]. The anti-diabetic drug trelagliptin induces vasodilation via activation of Kv channels and SERCA pumps. Life Sci. 2021;283:119868.

[2]. Glyburide Regulates UCP1 Expression in Adipocytes Independent of KATP Channel Blockade. iScience. 2020;23(9):101446.

[3]. P-glycoprotein inhibition by glibenclamide and related compounds. Pflugers Arch. 1999;437(5):652-660.

[4]. Glibenclamide interferes with mitochondrial bioenergetics by inducing changes on membrane ion permeability. J Biochem Mol Toxicol. 2004;18(3):162-169.

[5]. Glibenclamide-Induced Autophagy Inhibits Its Insulin Secretion-Improving Function in β Cells. Int J Endocrinol. 2019;2019:1265175.

Glyburide is an N-sulfonylurea that is acetohexamide in which the acetyl group is replaced by a 2-(5-chloro-2-methoxybenzamido)ethyl group. It has a role as a hypoglycemic agent, an anti-arrhythmia drug, an EC 2.7.1.33 (pantothenate kinase) inhibitor and an EC 3.6.3.49 (channel-conductance-controlling ATPase) inhibitor. It is a N-sulfonylurea and a member of monochlorobenzenes.
Glyburide is a second generation sulfonylurea used to treat patients with diabetes mellitus type II. It is typically given to patients who cannot be managed with the standard first line therapy, [metformin]. Glyburide stimulates insulin secretion through the closure of ATP-sensitive potassium channels on beta cells, raising intracellular potassium and calcium ion concentrations. Glyburide was granted FDA approval on 1 May 1984. A formulation with metformin was granted FDA approval on on 31 July 2000.
Glyburide is a Sulfonylurea.
Glyburide is a sulfonamide urea derivative with antihyperglycemic activity that can potentially be used to decrease cerebral edema. Upon administration, glyburide binds to and blocks the sulfonylurea receptor type 1 (SUR1) subunit of the ATP-sensitive inwardly-rectifying potassium (K(ATP)) channels on the membranes of pancreatic beta cells. This prevents the inward current flow of positively charged potassium (K+) ions into the cell, and induces a calcium ion (Ca2+) influx through voltage-sensitive calcium channels, which triggers exocytosis of insulin-containing granules. In addition, glyburide also inhibits the SUR1-regulated nonselective cation (NC) Ca-ATP channel, melastatin 4 (transient receptor potential cation channel subfamily M member 4; (TRPM4)), thereby preventing capillary failure and brain swelling. SUR1-TRPM4 channels are formed by co-assembly of SUR1 with TRPM4 in neurons, astrocytes, and capillary endothelium during cerebral ischemia. Upon ischemia-induced ATP depletion, channels open which results in sodium influx, cytotoxic edema formation, capillary fragmentation and necrotic cell death. SUR1-TRPM4 is not expressed in normal, uninjured tissues.
An antidiabetic sulfonylurea derivative with actions like those of chlorpropamide
See also: Glyburide; Metformin Hydrochloride (component of).

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Drug Indication
Glyburide is indicated alone or as part of combination product with metformin, as an adjunct to diet and exercise, to improve glycemic control in adults with type 2 diabetes mellitus.
Amglidia is indicated for the treatment of neonatal diabetes mellitus, for use in newborns, infants and children. Sulphonylureas like Amglidia have been shown to be effective in patients with mutations in the genes coding for the β-cell ATP-sensitive potassium channel and chromosome 6q24-related transient neonatal diabetes mellitus.
Treatment of large hemispheric infarction
Treatment of neonatal diabetes mellitus

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Mechanism of Action
Glyburide belongs to a class of drugs known as sulfonylureas. These drugs act by closing ATP-sensitive potassium channels on pancreatic beta cells. The ATP-sensitive potassium channels on beta cells are known as sulfonylurea receptor 1 (SUR1). Under low glucose concentrations, SUR1 remains open, allowing for potassium ion efflux to create a -70mV membrane potential. Normally SUR1 closes in response to high glucose concentrations, the membrane potential of the cells becomes less negative, the cell depolarizes, voltage gated calcium channels open, calcium ions enter the cell, and the increased intracellular calcium concentration stimulates the release of insulin containing granules. Glyburide bypasses this process by forcing SUR1 closed and stimulating increased insulin secretion.

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Pharmacodynamics
Glyburide is a second generation sulfonylurea that stimulates insulin secretion through the closure of ATP-sensitive potassium channels on beta cells, raising intracellular potassium and calcium ion concentrations. Glibenclamide has a long duration of action as it is given once daily, and a wide therapeutic index as patients are started at doses as low as 0.75mg but that can increase as high as 10mg or more. Patients taking glyburide should be cautioned regarding an increased risk of cardiovascular mortality as seen with tolbutamide, another sulfonylurea.

C23H28CLN3O5S

494

493.143

C, 55.92; H, 5.71; Cl, 7.18; N, 8.51; O, 16.19; S, 6.49

10238-21-8

Glyburide-d3;1219803-02-7;Glyburide-d11;1189985-02-1; 52169-36-5 (potassium salt)

3488

White to off-white solid powder

1.4±0.1 g/cm3

705.7±70.0 °C at 760 mmHg

173-175°C

380.6±35.7 °C

0.0±2.4 mmHg at 25°C

1.623

5.19

3

5

8

33

746

0

ZNNLBTZKUZBEKO-UHFFFAOYSA-N

InChI=1S/C23H28ClN3O5S/c1-32-21-12-9-17(24)15-20(21)22(28)25-14-13-16-7-10-19(11-8-16)33(30,31)27-23(29)26-18-5-3-2-4-6-18/h7-12,15,18H,2-6,13-14H2,1H3,(H,25,28)(H2,26,27,29)

5-chloro-N-[2-[4-(cyclohexylcarbamoylsulfamoyl)phenyl]ethyl]-2-methoxybenzamide

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)

Solubility in Formulation 1: ≥ 2.08 mg/mL (4.21 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (4.21 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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