Endogenous Metabolite; HDAC; Microbial Metabolite
Sodium butyrate has multiple targets. Its primary and most well-studied mechanism of action is as a histone deacetylase (HDAC) inhibitor. By inhibiting HDACs, it increases histone acetylation, leading to changes in chromatin structure and gene expression. It also serves as an energy metabolite, providing ATP to cells, and acts as an activator of G protein-coupled receptors (GPCRs). This multi-faceted mechanism of action is responsible for its broad range of biological effects.

Sodium butyrate (NaB), the sodium salt form of butyrate commonly used in pharmacological studies, is a well-known HDAC inhibitor that results in increased histone acetylation when applied to cells in culture in the high micromolar range [1].
Sodium butyrate is a well-known HDAC inhibitor that results in increased histone acetylation when applied to cells in culture. This leads to the modulation of gene expression, affecting various cellular processes such as cell cycle arrest, differentiation, and apoptosis. Its anticancer activity has been demonstrated in numerous in vitro studies across a wide range of cancer cell lines. It is also used to induce cell differentiation in culture.

Numerous subsequent studies have shown that NaB’s salutary effects span many neurological disease models and aspects of the pathophysiology of disease. For example, NaB can protect neurons from cell death in models of Parkinson’s disease and in cisplatin-induced hearing loss, where NaB was able to reverse the disease-associated reduction in histone acetylation. Similarly, NaB was able to reduce the infarct size in models of ischemic stroke, limiting the damage to the brain and improving behavioral outcomes. In vitro and in vivo (via intraperitoneal injection) data from our own laboratory also suggests that butyrate can induce resistance to oxidative stress and increase histone acetylation and enhance gene expression of a number of genes in the high micromolar range. Altogether, these observations are consistent with the idea that NaB can modulate the expression of a large number of genes to affect numerous pathophysiological pathways. The prospect of accomplishing this goal with a single, naturally occurring small molecule is exciting.[1]
Sodium butyrate has been shown to have beneficial effects in numerous in vivo models. For example, it can protect neurons from cell death in models of Parkinson's disease and reverse the disease-associated reduction in histone acetylation. It has also been shown to reduce infarct size in models of ischemic stroke, limiting brain damage and improving behavioral outcomes. Furthermore, it can induce resistance to oxidative stress and increase histone acetylation and gene expression in vivo. These observations suggest that sodium butyrate can modulate the expression of a large number of genes to affect numerous pathophysiological pathways.

In vitro assays for sodium butyrate typically involve treating cells in culture and measuring its effects on histone acetylation, gene expression, cell viability, or differentiation. A common assay is to treat cells with varying concentrations of sodium butyrate and then measure the level of histone acetylation by Western blot using an anti-acetylated histone antibody. Cell viability can be assessed using standard assays like MTT or CellTiter-Glo. Gene expression changes can be measured by qPCR or RNA-seq.

Cellular assays for sodium butyrate are performed using a wide variety of cell lines, including cancer cells, immune cells, and neuronal cells. Cells are treated with sodium butyrate at concentrations typically in the high micromolar range. The effects on cell proliferation, apoptosis, differentiation, and cytokine production are then assessed. For example, its ability to induce differentiation in malignant cells can be studied in leukemia cell lines.

Sodium butyrate has been studied in numerous in vivo animal models. It can be administered via various routes, including intraperitoneal injection. In a clinical pharmacological study, it was administered intravenously to patients at a dose of 500 mg/kg/day for 10 days. Its effects on various disease models, such as Parkinson's disease, stroke, and cancer, have been investigated, demonstrating its broad therapeutic potential.

Absorption, Distribution and Excretion
Since cancer can be considered a differentiated disease, and sodium butyrate can induce malignant cell differentiation in vitro, a clinical pharmacological study of sodium butyrate was conducted. Nine patients were included: acute myeloid leukemia (n=1), acute monocytic leukemia (n=1), acute myelomonocytic leukemia (n=6), and acute undifferentiated leukemia (n=1). The median age of the patients was 52 years (range 27–78 years). Six of the nine patients had previously received cytosolic inhibitor pretreatment. Sodium butyrate was administered intravenously at a dose of 500 mg/kg/day for 10 days. A sensitive and reproducible high-performance liquid chromatography (HPLC) method was established using a crown ether catalyst to derivatize sodium butyrate with 2,4'-dibromoacetophenone. Plasma sodium butyrate concentrations and urinary excretion were monitored during the 10-day continuous infusion of sodium butyrate and for 2 days after the infusion ended. During infusion, plasma sodium butyrate concentration increased 6-fold compared to endogenous sodium butyrate levels, reaching 39-59 μM. The area under the curve (AUC) for exogenous sodium butyrate was 384 ± 50 μM·day (mean ± standard deviation). After infusion, sodium butyrate concentration decreased rapidly with a half-life of 6.1 ± 1.4 minutes, returning to pre-infusion levels within 1 hour. Total clearance was 83 ± 12 ml/kg/min, and volume of distribution was 738 ± 245 ml/kg. Urinary excretion of sodium butyrate was minimal compared to the infused dose. While excretion through other organs could not be ruled out, this suggests rapid metabolism of the infused sodium butyrate. A significant increase in peripheral blood blasts was observed, while bone marrow cytology showed no significant change in blasts before and after treatment. Peripheral blood leukocyte count showed no significant change. No toxic reactions were observed. The poor clinical efficacy may be due to the short half-life of sodium butyrate in vivo, resulting in low plasma concentrations. In contrast, in vitro studies reported concentrations that were at least 10 times higher.
Sodium butyrate is a small, naturally occurring molecule. In a clinical study, it was administered intravenously at a dose of 500 mg/kg/day. A sensitive and reproducible HPLC method was established to measure its levels. As a short-chain fatty acid, it is rapidly absorbed and metabolized. Its half-life is short, and it is cleared quickly from the circulation.

Interactions
Sodium butyrate-induced alkaline phosphatase activity in HeLa cells can be inhibited by co-administration of caffeine or theophylline. Sodium butyrate and dimethyl sulfoxide significantly affected the growth, morphology, and biochemical characteristics of two human colon adenocarcinoma cell lines. Doubling time was prolonged by 18% to 660%, while cell viability was unaffected. Sodium butyrate combined with interferon enhanced the antitumor effect of interferon in vivo. When sarcoma 180 TG cells were inoculated into mice, the mean survival time and final survival rate were significantly improved compared to mice treated with interferon alone. Sodium butyrate, when used in combination with therapeutic agents (X-rays, fluorouracil, lomustine, vincristine, doxorubicin sulfate, 5-(3,3-dimethyl-1-triazenoyl)imidazol-4-carboxamide, or methotrexate) or cyclic adenosine monophosphate stimulants (RO 20-1724, theophylline, papaverine, or prostaglandin E1), further reduced… The number of cells in mouse neuroblastoma cultures was significantly increased compared to the use of each agent alone. Treatment of Epstein-Barr virus-producing and non-producing cell lines with a combination of phorbol 12-myristate 13-acetate and sodium butyrate resulted in significant hypomethylation (approximately 30%) of the DNA in the Epstein-Barr virus-producing cell line P3HR-1 when DNA replication was inhibited.
Sodium butyrate is generally well-tolerated, but its clinical use can be limited by its short half-life and the need for high doses. In the clinical study, it was administered intravenously. Common side effects may include gastrointestinal disturbances. Its safety profile has been established through numerous preclinical and clinical studies.

[1]. Neurosci Lett. 2016 Jun 20; 625: 56–63.

Sodium butyrate is an organic sodium salt formed by replacing the proton on the carboxyl group of butyrate with a sodium ion. It is an EC 3.5.1.98 (histone deacetylase) inhibitor and an anti-aging agent. It contains the butyrate ion. Sodium butyrate is the sodium salt of butyrate and has potential antitumor activity. Butyrate is a short-chain fatty acid that competitively binds to the zinc binding sites of class I and II histone deacetylases (HDACs). This binding affects the excessive acetylation of histones, leading to DNA conformational changes, which in turn cause chromatin unwinding or relaxation. Increased chromatin accessibility to transcriptional regulatory complexes leads to enhanced transcriptional activation of various epigenetic repressor genes. Butyrate is an HDAC inhibitor that can induce cell cycle arrest at G1 or G2/M phases and increase the expression of other genes and proteins involved in cell differentiation and apoptosis signaling. Butyrate is a tetracarbonate with the chemical formula CH3CH2CH2COOH, has an unpleasant odor, and exists in butter and animal fats in the form of glycerides.

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Mechanism of Action
Sodium butyrate inhibits the initiation of viral and cellular DNA replication in polyomavirus-infected mouse kidney cells.
Twenty-four hours after treatment of Friends erythroleukemia cells with millimolecular concentrations of sodium butyrate, chromatin histones undergo hyperacetylation. During the same period, butyrate-treated FFriend cells accumulated approximately 38% of new RNA transcripts synthesized from unique sequences of mouse DNA.
F9 mouse teratoma stem cells differentiate into parietal endoderm cells in the presence of retinoic acid, dibutyryl cyclic adenosine monophosphate (DAMP), and theophylline. When F9 cells are exposed to 2–5 mM sodium butyrate, along with retinoic acid, DAMP, and theophylline, they fail to differentiate. Butyrate only inhibits differentiation when added within 8 hours of retinoic acid addition. Therefore, the early events of retinoid action on F9 cells are sensitive to butyrate. Butyrate inhibits histone deacetylation in F9 cells, which may be the mechanism by which butyrate inhibits cell differentiation. Sodium butyrate treatment promotes the development and progression of colon cancer and is associated with increased butyrate concentrations in the feces of rats parenterally administered 1,2-dimethylhydrazine. DNA polymerase inhibitors effectively suppress initiator-induced amplification of the SV40 DNA sequence in the SV40-transformed Chinese hamster cell line CO631. Sodium butyrate inhibits DNA synthesis through histone modification.
Sodium butyrate is a short-chain fatty acid with profound beneficial effects on brain disorders, ranging from neurodegenerative diseases to psychological disorders. It is a histone deacetylase (HDAC) inhibitor, an energy metabolite, and a GPCR activator. Its ability to modulate gene expression and cellular metabolism makes it a promising therapeutic molecule for a wide range of diseases.

C4H7NAO2

110.086952447891

110.034

156-54-7

5222465

White to off-white solid powder

0.987g/cm3

164.3ºC at 760 mmHg

250-253 °C(lit.)

69.7ºC

1.35mmHg at 25°C

0

2

2

7

53.7

0

[Na+].[O-]C(CCC)=O

MFBOGIVSZKQAPD-UHFFFAOYSA-M

InChI=1S/C4H8O2.Na/c1-2-3-4(5)6;/h2-3H2,1H3,(H,5,6);/q;+1/p-1

sodium;butanoate

SODIUM BUTYRATE; 156-54-7; Butyrate sodium; Sodium butanoate; Butyric acid sodium salt; Butanoic acid, sodium salt; Butyric acid, sodium salt; Sodium n-butyrate;

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)

H2O: ~100 mg/mL (~908 mM)

PBS: ~100 mg/mL (~908 mM) (Please use freshly prepared in vivo formulations for optimal results.)