Currently, brain natriuretic peptide (BNP) and em N /em -terminal proBNP (NT-proBNP) are trusted simply because diagnostic biomarkers for heart failure (HF) and cardiac dysfunction in clinical medicine. serious global open public health issues. The global burden of HF and cardiac dysfunction is certainly increasing quickly and considerably SGI-1776 pontent inhibitor with the maturing of the populace [1,2,3,4,5,6]. Because of high morbidity and mortality, the medical diagnosis of HF and cardiac dysfunction is really important in both scientific and forensic medication [7,8,9,10]. For inpatients, the medical diagnosis of HF and cardiac dysfunction could be coupled with clinically assisted examinations, such as for example electrocardiography or echocardiography. Nevertheless, for the deceased examined by forensic pathologists, the medical diagnosis of HF or the evaluation of cardiac function after loss of life is quite difficult because of the insufficient clinical medical information of SGI-1776 pontent inhibitor the deceased and unavailability of assisted examinations. Postmortem evaluation and diagnosis, specifically for HF or cardiac dysfunction of the deceased without regular visible morphological adjustments, are really challenging [10]. Human brain natriuretic peptide (BNP) and em N /em -terminal proBNP (NT-proBNP) are trusted as significant indicators for the scientific medical diagnosis of HF and cardiac dysfunction [11,12,13,14,15,16,17]. Recently, many forensic studies have demonstrated that BNP and NT-proBNP could be used to reflect the cardiac function of the deceased before their death through extensive animal experiments and postmortem specimens, and they could also be used as postmortem biomarkers for the diagnosis of HF or cardiac dysfunction in forensic medicine [9,10,18,19,20]. However, few articles have reviewed application of BNP and NT-proBNP in forensic medicine. For this purpose, this article reviews the biological features, the clinical and forensic research, and the application status of BNP and NT-proBNP, as well as their future research prospects in order to provide useful assistance for clinicians and forensic pathologists. 2. Biological Features of BNP and NT-proBNP The natriuretic peptide family mainly includes atrial natriuretic peptide SGI-1776 pontent inhibitor (ANP), which is mostly synthesized and secreted by atrial myocytes, BNP, and C-type natriuretic peptide (CNP) [21]. BNP was originally isolated from pig brain tissue in 1988 and was named brain natriuretic peptide, but subsequent studies have shown that its synthesis and secretion are mainly in ventricular myocytes [22]. 2.1. Structure, Synthesis, and Secretion of BNP and NT-proBNP BNP is mainly synthesized and secreted by myocytes in the left ventricle (LV) as a response to myocytes stretched by pressure overload or volume expansion of the ventricle [12,23,24,25,26]. The structure of BNP is usually highly conserved among different species, and the difference between different species is usually in the length and amino acid composition of the em N /em -terminal and em C /em -terminal tail chains [27]. Human BNP is usually TSHR a 32 amino acid polypeptide containing a 17 amino acid ring structure with a disulfide bond connecting two cysteine residues [28,29]. The human gene encoding BNP is located on chromosome 1, and the mRNA encoding BNP contains an unstable repeat TATTTAT sequence [28,30,31]. Instead of storage in normal physiological myocardial tissue, the transcription of BNP mRNA and the synthesis and secretion of BNP protein occur SGI-1776 pontent inhibitor in an explosive way and are rapidly released into surrounding tissues after myocardial synthesis [30,32]. Under pathological conditions, the unstable mRNA can rapidly synthesize a 134 amino acid BNP precursor (pre-proBNP) and remove the em N /em -terminal 26 amino acid signal peptide to form a 108 amino acid BNP (proBNP), and then, proBNP is usually split by the proNP convertases, corin or furin, into an inactive 76-amino acid NT-proBNP and an active 32-amino acid BNP [24,33]. Both the biologically active BNP and NT-proBNP could be found in plasma [34,35]. 2.2. Receptors of Natriuretic Peptides There are three membrane-bound natriuretic peptide receptors (NPR) for natriuretic peptides, namely NPR-A, NPR-B, and NPR-C. NPR-A is usually abundant in the vascular endothelium system and some other organs such as kidney and brain [12,34]. NPR-A receptor is the main effector of both ANP and BNP actions,.