Branched-chain amino acid transporters and enzymes (BCAA transporters and enzymes)

Branched-chain amino acid (BCAA) transporters and enzymes constitute the metabolic machinery responsible for the uptake and catabolism of the essential amino acids leucine, isoleucine, and valine [8, 15]. This system includes transporters such as the Large Neutral Amino Acid Transporter 1 (LAT1/SLC7A5) and enzymes like Branched-Chain Amino Acid Aminotransferase (BCAT1/2) and the Branched-Chain Alpha-Keto Acid Dehydrogenase (BCKDH) complex [7, 15]. These components play a critical role in regulating protein synthesis, nutrient sensing via the mTORC1 pathway, and energy homeostasis [6, 10, 11]. Dysregulation of BCAA metabolism is linked to various pathologies, including insulin resistance, obesity, and several types of cancer where BCAT1 is often overexpressed to support rapid proliferation [1, 3, 12]. Therapeutic strategies involve inhibiting transporters like LAT1 to starve cancer cells or modulating enzyme activity, such as using BCKDK inhibitors (e.g., BT2) to activate the BCKDH complex and lower elevated BCAA levels in metabolic diseases [4, 9, 15]. Clinical candidates like JPH203 target the transport phase, while experimental compounds like BAY-069 target the enzymatic transamination step [4, 14, 15]. Overall, this target group represents a key metabolic node for intervention in oncology and metabolic medicine [5, 7, 10].

Other names

BCAA metabolic pathwayBCAA catabolic machineryBranched-chain amino acid metabolic enzymes and transportersBCAA catabolic pathway

Inhibition of BCAA transamination by BCAT inhibitors, activation of the BCKDH complex via BCKDK inhibition to enhance BCAA catabolism, or blockade of large neutral amino acid transporters (LAT1) to restrict cellular BCAA uptake and inhibit downstream mTORC1 signaling.