C-type natriuretic-derived peptides as biomarkers in human disease

Recent Advances in Individualized Clinical Strategies for Polycystic Ovary Syndrome: Evidence From Clinical Trials and Emerging Pharmacotherapies

PURPOSE

Clinical trials are advancing the treatment of polycystic ovary syndrome (PCOS), an endocrine disorder affecting 8-13% of women. Lifestyle interventions, including nutritional plans, physical activity, and stress management, can improve reproductive hormones and metabolic health. Novel pharmacotherapies targeting hormonal, metabolic, and reproductive abnormalities are being explored for individualized treatment. Combination therapies and lifestyle interventions like acupuncture, high-intensity interval training, and vitamin D3 supplementation are also being explored.

METHODS

We conducted a narrative review by searching English-language studies across electronic databases such as PubMed, Science direct, and Google Scholar for articles related to the topics of PCOS and novel drug therapies such as metformin, LIK-066, elagolix, saxenda, exenatide, clomiphene, letrozole, and other diagnostic interventions. Our review excluded preclinical studies and articles not in english.

FINDINGS

In addition to pharmacological treatments, lifestyle interventions such as Tung's acupuncture, high-intensity interval training (HIIT), and vitamin D3 supplementation have proven effective in managing symptoms of PCOS and enhancing overall health outcomes. These interventions offer a complementary approach to traditional medical therapies, emphasizing the importance of integrating lifestyle modifications into the treatment plan for women with PCOS.

IMPLICATIONS

This comprehensive approach underscores the importance of tailored treatments in optimizing clinical outcomes and quality of life for women with PCOS. The aim of this review is to highlight recent advancements in the treatment of PCOS through clinical trials and emerging pharmacotherapies, emphasizing the need for individualized and multifaceted treatment approaches.

CNP Ameliorates Macrophage Inflammatory Response and Atherosclerosis

BACKGROUND

CNP (C-type natriuretic peptide), an endogenous short peptide in the natriuretic peptide family, has emerged as an important regulator to govern vascular homeostasis. However, its role in the development of atherosclerosis remains unclear. This study aimed to investigate the impact of CNP on the progression of atherosclerotic plaques and elucidate its underlying mechanisms.

METHODS

Plasma CNP levels were measured in patients with acute coronary syndrome. The potential atheroprotective role of CNP was evaluated in apolipoprotein E-deficient (ApoE-/-) mice through CNP supplementation via osmotic pumps, genetic overexpression, or LCZ696 administration. Various functional experiments involving CNP treatment were performed on primary macrophages derived from wild-type and CD36 (cluster of differentiation 36) knockout mice. Proteomics and multiple biochemical analyses were conducted to unravel the underlying mechanism.

RESULTS

We observed a negative correlation between plasma CNP concentration and the burden of coronary atherosclerosis in patients. In early atherosclerotic plaques, CNP predominantly accumulated in macrophages but significantly decreased in advanced plaques. Supplementing CNP via osmotic pumps or genetic overexpression ameliorated atherosclerotic plaque formation and enhanced plaque stability in ApoE-/- mice. CNP promoted an anti-inflammatory macrophage phenotype and efferocytosis and reduced foam cell formation and necroptosis. Mechanistically, we found that CNP could accelerate HIF-1α (hypoxia-inducible factor 1-alpha) degradation in macrophages by enhancing the interaction between PHD (prolyl hydroxylase domain-containing protein) 2 and HIF-1α. Furthermore, we observed that CD36 bound to CNP and mediated its endocytosis in macrophages. Moreover, we demonstrated that the administration of LCZ696, an orally bioavailable drug recently approved for treating chronic heart failure with reduced ejection fraction, could amplify the bioactivity of CNP and ameliorate atherosclerotic plaque formation.

CONCLUSIONS

Our study reveals that CNP enhanced plaque stability and alleviated macrophage inflammatory responses by promoting HIF-1α degradation, suggesting a novel atheroprotective role of CNP. Enhancing CNP bioactivity may offer a novel pharmacological strategy for treating related diseases.

Mobility of antipyretic drugs with different molecular structures in saturated soil porous media

In the post-COVID-19 era, extensive quantities of antipyretic drugs are being haphazardly released from households into the environment, which may pose potential risks to ecological systems and human health. Identification of the mobility behaviors of these compounds in the subsurface environment is crucial to understand the environmental fate of these common contaminants. The mobility properties of three broad-spectrum antipyretic drugs, including ibuprofen (IBF), indometacin (IMC), and acetaminophen (APAP), in porous soil media, were investigated in this study. The results showed that the mobility of the three drugs (the background electrolyte was Na+) through the soil column followed the order of APAP > IBF > IMC. The difference in the physicochemical characteristics of various antipyretic drugs (e.g., the molecular structure and hydrophobicity) could explain this trend. Unlike Na+, Ca2+ ions tended to serve as bridging agents by linking the soil grains and antipyretic molecules, leading to the relatively weak mobility behaviors of antipyretic drugs. Furthermore, for a given antipyretic drug, the antipyretic mobility was promoted when the background solution pH values were raised from 5.0 to 9.0. The phenomenon stemmed from the improved electrostatic repulsion between the dissociated species of antipyretic molecules and soil grains, as well as the weakened hydrophobic interactions between antipyretic drugs and soil organic matter. Furthermore, a two-site non-equilibrium transport model was used to estimate the mobility of antipyretic drugs. The results obtained from this work provide vital information illustrating the transport and retention of various antipyretic drugs in aquifers.

N-Terminal Pro-C-Type Natriuretic Peptide: The Novel Marker in Selected Disease Units

BACKGROUND

Amino-terminal pro C type natriuretic peptide (NT proCNP) is the N terminal fragment of the CNP precursor. NT proCNP occurs in an equimolar concentration with CNP in human plasma and is considered to be a marker of the extent of CNP biosynthesis. A recent study has shown associations between plasma NT proCNP and blood pressure; it is also an independent predictor of death and cardiac readmission in people with unstable angina. Beyond that, recent studies have focused on the applicability of assessing NT proCNP peptide levels in the diagnosis of diseases with different etiologies but the same denominator, i.e., inflammation.

METHODS

This study reviewed recent results on the usability of NT proCNP peptide levels in the diagnosis of diseases accompanied by statistical analysis of previously reported results.

RESULTS

The data obtained confirmed the applicability of the assessment of NT proCNP levels in biological fluids in diseases, such as Parkinson's disease, sepsis, meningitis, and asthenozoospermia.

CONCLUSION

The reported results demonstrated that NT-proCNP is helpful in a variety of diseases. Furthermore, changes in serum or CSF levels of NT-proCNP reflect only inflammatory states related to general inflammation. Local inflammation does not trigger an increase in NT proCNP level.

Processing-independent analysis (PIA): a method for quantitation of the total peptide-gene expression

The translational product of protein-coding genes undergoes extensive posttranslational modifications. The modifications ensure an increased molecular and functional diversity at protein- and peptide-level. Prohormones are small pro-proteins that are expressed in many cell types, for instance endocrine cells, immune cells, myocytes and neurons. Here they mature to bioactive peptides (cytokines, hormones, growth factors, and neurotransmitters) that are released from the cells in an often regulated manner. The posttranslational processing of prohormones is cell-specific, however, and may vary during evolution and disease. Therefore, it is often inadequate to measure just a single peptide fragment as marker of endocrine, immune, and neuronal functions. In order to meet this challenge, we developed years back a simple "processing-independent analysis" (PIA) for accurate quantification of the total pro-protein product - irrespective of the degree and nature of the posttranslational processing. This review provides an overview of the PIA principle and describes examples of PIA results in different peptide systems.

Circulating products of C-type natriuretic peptide and links with organ function in health and disease

Paracrine actions of CNP and rapid degradation at source severely limit study of CNP's many roles in vivo. However provided sensitive and validated assays are used, there is increasing evidence that low concentrations of bioactive CNP in plasma, and the readily detectable concentrations of the bio-inactive processed product of proCNP (aminoterminal proCNP), can be used to advance understanding of the hormone's role in pathophysiology. Provided renal function is normal, concordant changes in both CNP and NTproCNP reflect change in tissue production of proCNP whereas change in CNP alone results from altered rates of bioactive CNP degradation and are reflected in the ratio of NTproCNP to CNP. As already shown in juveniles, where plasma concentration of CNP products are higher and are associated with concurrent endochondral bone growth, measurements of plasma CNP products in mature adults have potential to clarify organ response to stress and injury. Excepting the role of CNP in fetal-maternal welfare, this review examines evidence linking plasma CNP products with function of a wide range of tissues in adults, including the impact of extraneous factors such as nutrients, hormone therapy and exercise.

Analogs of C-type natriuretic peptide as a potential new non-surgical treatment strategy in knee osteoarthritis

Osteoarthritis (OA) is a common, chronic, progressive, and multifactorial musculoskeletal system disease affecting millions of people around the world. Despite the use of several treatment modalities, the search for a disease modifying drug continuous. Recent evidence suggest involvement of C-type natriuretic peptide (CNP) signaling in induction of chondroprotective pathways. A CNP analog (BMN 111) with an extended plasma half-life due to its neutral-endopeptidase resistance has shown to be pharmacologically active in achondroplasia enabling to hypothesize that BMN 111 may also be used as a treatment strategy in OA, in which CNP signaling has been suggested to be protective and/or reparative.

Plasma C-Type Natriuretic Peptide: Emerging Applications in Disorders of Skeletal Growth

Although studies in experimental animals show that blood levels of C-type natriuretic peptide (CNP) and its bioinactive aminoterminal propeptide (NTproCNP) are potential biomarkers of long bone growth, a lack of suitable assays and appropriate reference ranges has limited the application of CNP measurements in clinical practice. Plasma concentrations of the processed product of proCNP, NTproCNP - and to a lesser extent CNP itself - correlate with concurrent height velocity throughout all phases of normal skeletal growth, as well as during interventions known to affect skeletal growth in children. Since a change in levels precedes a measurable change in height velocity during interventions, measuring NTproCNP may have predictive value in clinical practice. Findings from a variety of genetic disorders affecting CNP signaling suggest that plasma concentrations of both peptides may be helpful in diagnosis, provided factors such as concurrent height velocity, feedback regulation of CNP, and differential changes in peptide clearance are considered when interpreting values. An improved understanding of factors affecting plasma levels, and the availability of commercial kits enabling accurate measurement using small volumes of plasma, can be expected to facilitate potential applications in growth disorders including genetic causes -affecting the CNP signaling pathway.

Impacts of macrophage colony-stimulating factor (M-CSF) on the expression of natriuretic peptide precursor type C (NPPC) and regulation of meiotic resumption

In mammalian follicles, oocytes are arrested at the diplotene stage of prophase I until meiotic resumption following the LH surge. C-type natriuretic peptide (CNP), encoded by natriuretic peptide precursor type C (NPPC), was found to be reduced by the LH surge in the follicle, and then lead to meiotic resumption by decreasing the level of cAMP in the oocyte. As a wide-spread cytokine, macrophage colony-stimulating factor (M-CSF) takes part in the oocyte development to maturation and ovulation. Our study describes the expression curve of M-CSF and its receptor and investigates the impact on the levels of CNP/NPPC to explore the possible mechanism for meiotic resumption in both vivo and vitro. The result shows after the LH/HCG surge, the expressions of M-CSF and its receptors decline significantly inside ovarian follicles, thus leading to transduction of a range of signals. Consequently, the expression of CNP reaches the peak at 2 h and immediately declines to a relatively low level.

Plasma Amino-Terminal Propeptide of C-Type Natriuretic Peptide Concentration in Normal-Weight and Obese Children

OBJECTIVE

In studies on the relationship between amino-terminal propeptide of C-type natriuretic peptide (NT-proCNP) concentration and height velocity in children, CNP has been implicated as an emerging new growth marker during childhood. It has been reported that besides its well-studied role in growth, plasma CNP levels are reduced in overweight and/or obese adolescents, suggesting CNP as a potential biomarker in childhood obesity. The primary goal of this study was to test this hypothesis in a Turkish population.

METHODS

Consent was taken from 317 children [ages 0-18 (158 girls, 159 boys)] and their parents. All subjects were physically examined; anthropometric measurements were obtained. Body mass index was calculated. During routine blood work, 1 mL extra blood was taken. Plasma NT-proCNP concentration was measured by enzyme-linked immunosorbent assay.

RESULTS

Results confirmed the previously described relationship between plasma NT-proCNP concentration and growth velocity. Plasma NT-proCNP concentration showed a negative correlation with age, weight, and height in children. Gender was not a factor that alters the age-dependent plasma NT-proCNP concentration until puberty.

CONCLUSION

Unlike previous reports, plasma NT-proCNP concentration of overweight/obese children was not significantly lower than that of children with normal weight in age groups analyzed in a Turkish population. Thus, it is too early to conclude that CNP is a potential biomarker in childhood obesity. Further studies are necessary to address this question.

N-terminal pro-C-type natriuretic peptide in serum associated with bone destruction in patients with multiple myeloma

Aim: To examine whether N-terminal proCNP concentrations in serum is associated with bone destruction in patients with multiple myeloma. Materials & methods: N-terminal proCNP and biochemical bone markers were measured in 153 patients. Radiographic bone disease and skeletal-related events were evaluated at specific time-points. Results: N-terminal proCNP concentrations increased with age. High N-terminal proCNP concentrations were associated with high-risk disease and renal impairment. Renal function explained 22% of the variation. N-terminal proCNP concentrations correlated with serum bone ALP and serum PINP, but lacked association with bone resorption markers, radiographic bone disease and skeletal-related events. Conclusion: Serum N-terminal proCNP are associated with bone formation activity in patients with multiple myeloma, but should be interpreted with caution in patients with renal impairment.

Cardiac C-type natriuretic peptide gene expression and plasma concentrations in neonatal piglets

BACKGROUND

C-type natriuretic peptide (CNP) is a member of the natriuretic peptide family. Cardiac ANP and BNP expressions are firmly established, whereas CNP expression in the mammalian heart remains controversial. In the present report, we used a porcine model of the neonatal period with high expressions of cardiac ANP and BNP in order to elucidate the cardiac CNP expression profile.

METHODS

Plasma and cardiac tissue were obtained from newborn piglets during the first 72 h of life. The chamber-specific CNP mRNA contents were quantified by real-time PCR analysis. The proCNP concentrations in plasma and cardiac tissue extracts were quantified by a porcine-specific radioimmunoassay.

RESULTS

Cardiac CNP mRNA contents (n=24) were low compared to sites of known expression, where porcine seminal vesicle CNP mRNA contents were 200-fold higher. In addition, plasma proCNP concentrations in the newborn piglets (n=44) were exceedingly low compared to proANP concentrations (5.3 pmol/L (3.2-8.6) vs. 3438 pmol/L (2790-5418), p<0.0001). The proCNP concentrations in atrial tissue extracts were barely detectable (≤0.06 pmol/g) (n=2) compared to ventricular proANP (130 pmol/g (101-159)) and atrial proANP (12,303 pmol/g (10,623-15,412)).

CONCLUSION

Our data show that the heart is not a major source of circulating proCNP in neonatal piglets.