Biology subjects

Natale, C. A.

Publications and source records attributed to Natale, C. A..

7 recordsLinked to original sources

bioRxiv2025

Pregnancy-Dependent Cardioprotection via GPER Activation in Dahl Salt-Sensitive Rats

BackgroundPreeclampsia is a hypertensive disorder of pregnancy that affects multiple organs, including the heart, increasing long-term cardiovascular risks for both the mother and offspring. While the G protein-coupled estrogen receptor (GPER) has cardioprotective effects, its role in pregnancy-associated cardiac dysfunction, particularly in chronic hypertension, remains unclear, given the significant physiological adaptations that occur during pregnancy, including hormonal fluctuations and hemodynamic changes. This study investigated whether LNS8801, a selective and orally bioavailable GPER agonist, could improve cardiac function in virgin and pregnant Dahl salt-sensitive (SS/Jr) rats, a model of chronic hypertension exacerbated by pregnancy. MethodsFemale Dahl SS/Jr rats, both virgin and pregnant, were randomized into four groups: Virgin + Vehicle, Virgin + LNS8801, Pregnant + Vehicle, and Pregnant + LNS8801. LNS8801 (800 {micro}g/kg/day, given orally) was administered in pregnant rats from gestational day (GD) 9 to 20 and for an equivalent period in virgin controls. Cardiac function was assessed via echocardiography, including speckle-tracking strain analysis and conventional systolic and diastolic parameters. Mean arterial pressure and proteinuria were also measured. ResultsLNS8801 significantly improved cardiac function in pregnant Dahl SS/Jr rats, enhancing global longitudinal, circumferential, and radial strain, as well as increasing systolic function. Additionally, LNS8801 enhanced diastolic function, improving left ventricular compliance (E/A ratio) and early mitral annular velocity (e'), while reducing left ventricular filling pressures (E/e' ratio). In contrast, LNS8801 had no significant effects on cardiac function and blood pressure in virgin Dahl SS/Jr rats, suggesting that pregnancy-related adaptations may enhance GPER-mediated cardioprotection. LNS8801 treatment significantly reduced proteinuria in both virgin and pregnant rats, indicating a pregnancy-independent renal protective effect. ConclusionThis study highlights the importance of pregnancy-specific adaptations in shaping the cardiovascular effects of GPER activation. While LNS8801 demonstrated cardioprotective and antihypertensive benefits in pregnant Dahl SS/Jr rats, its effects were absent in virgin animals, underscoring the influence of the physiological and hormonal environment on GPER-mediated responses. These findings provide a foundation for further exploration of GPER as a therapeutic target for pregnancy-associated cardiovascular dysfunction and preeclampsia, reinforcing the need for pregnancy-specific approaches in drug development.

pharmacology and toxicology↗

bioRxiv2024

LNS8801: An enantiomerically pure agonist of the G protein-coupled estrogen receptor suitable for clinical development

Estrogen effects in tissue are mediated in part through activation of the surface estrogen receptor GPER, a broadly expressed G protein-coupled receptor that impacts a wide range of normal and pathologic processes, including metabolism, vascular health, inflammation, and cancer. A commonly used synthetic and specific GPER agonist, named G-1, antagonizes tumors by promoting cellular differentiation and enhancing tumor immunogenicity. G-1 is a racemic compound, and since its discovery, the question of whether both enantiomers display agonist activity or the agonist activity resides primarily in a single enantiomer has never been fully resolved. Herein, we disclose the isolation of the pure enantiomers of G-1 and determine that the desirable activity resides exclusively in 1 enantiomer, named LNS8801, whose configuration we have unambiguously determined by single crystal x-ray structure analysis. Using preclinical models, we show that LNS8801 suppresses cancer in a GPER-dependent manner and that LNS8801 is efficacious when administered orally. Further, we show that GPER is widely, but not ubiquitously, expressed in both normal and malignant human tissues. In addition, an attenuated response to LNS8801 is observed in a common germline coding variant in human GPER. These findings support ongoing human cancer trials with LNS8801 and suggest that the germline GPER genotype may serve as a predictive biomarker of therapeutic response.

cancer biology↗

bioRxiv2023

Ovariectomy-Induced Arterial Stiffening Differs from Vascular Aging and is Reversed by GPER Activation

Arterial stiffness is a cardiovascular risk factor and dramatically increases as women transition through menopause. The current study assessed whether a mouse model of menopause increases arterial stiffness in a similar manner to aging, and whether activation of the G protein-coupled estrogen receptor (GPER) could reverse stiffness. Female C57Bl/6J mice were ovariectomized (OVX) at 10 weeks of age or aged to 52 weeks, and some mice were treated with GPER agonists. OVX and aging increased pulse wave velocity to a similar extent independent of changes in blood pressure. Aging increased carotid wall thickness, while OVX increased material stiffness without altering vascular geometry. RNA-Seq analysis revealed that OVX downregulated smooth muscle contractile genes. The enantiomerically pure GPER agonist, LNS8801, reversed stiffness in OVX mice to a greater degree than the racemic agonist G-1. In summary, OVX and aging induced arterial stiffening via potentially different mechanisms. Aging was associated with inward remodeling while OVX induced material stiffness independent of geometry and a loss of the contractile phenotype. This study helps to further our understanding of the impact of menopause on vascular health and identifies LNS8801 as a potential therapy to counteract this detrimental process in women.

pharmacology and toxicology↗

bioRxiv2023

Analysis of human GPER expression in normal tissues and select cancers using immunohistochemistry

GPER (G protein-coupled estrogen receptor) has been reported to play roles in several areas of physiology including cancer, metabolic disorders, and cardiovascular disease. However, the understanding of where this receptor is expressed in human tissue is limited due to limited available tools and methodologies that can reliably detect GPER protein. Recently, a highly specific monoclonal antibody against GPER (20H15L21) was developed and is suitable for immunohistochemistry. Using this antibody, we show that GPER protein expression varies markedly between normal human tissue, and also among cancer tissue. As GPER is an emerging therapeutic target for cancer and other diseases, this new understanding of GPER distribution will likely be helpful in design and interpretation of ongoing and future GPER research.

pathology↗

bioRxiv2021

Relative DOPA Deficiency in Lightly Pigmented Skin Contributes to UV-Independent Melanoma Susceptibility

Melanoma risk is 30 times higher in people with lightly pigmented skin compared to those with darkly pigmented skin. Here we show that this difference results from more than melanin pigment and its ultraviolet radiation (UVR) shielding effect. Using primary human melanocytes representing the full human skin pigment continuum and several preclinical melanoma models, we show that cell-intrinsic differences between dark and light melanocytes regulate melanocyte proliferative capacity, overall cellular differentiation state, and susceptibility to malignant transformation, independently of melanin and UV exposure. We determined that these differences result from dihydroxyphenylalanine (DOPA), a melanin precursor synthesized at higher levels in melanocytes from dark skin. Although DOPA was not previously known to have specific signaling activity, we used both high throughput pharmacologic and genetic in vivo CRISPR screens to determine that DOPA limits melanocyte and melanoma cell proliferation by directly inhibiting the muscarinic acetylcholine receptor M1 (CHRM1), a G Protein-Coupled Receptor (GPCR) not previously known to bind DOPA, nor to affect melanoma pathobiology. Pharmacologic CHRM1 antagonism in melanoma leads to depletion of c-Myc and FOXM1, both of which are proliferation drivers associated with aggressive melanoma. In preclinical mouse melanoma models using both immune deficient and syngeneic immune competent mice, pharmacologic inhibition of CHRM1 or FOXM1 inhibited tumor growth. CHRM1 and FOXM1 may be new therapeutic targets for melanoma.

cancer biology↗

bioRxiv2020

Nonclassical testosterone signaling through ZIP9 renders melanoma more aggressive in males than in females

Melanoma and most other cancers occur more frequently, and have worse prognosis, in males compared with females. Though sex steroids are thought to be involved, classical androgen and estrogen receptors are not detectable in most melanomas. Here we show that testosterone promotes melanoma proliferation by activating ZIP9 (SLC39A9), a zinc transporter that is not intentionally targeted by available therapeutics, but is widely expressed in human melanoma. This testosterone activity requires zinc influx, MAPK activation and YAP1 nuclear translocation. We demonstrate that FDA approved inhibitors of the classical androgen receptor also inhibit ZIP9, and thereby antagonize the pro-tumorigenic effects of testosterone in melanoma. In male mice, androgen receptor inhibitors suppressed growth of ZIP9-expressing melanomas, but had no effect on isogenic melanomas lacking ZIP9, nor on melanomas in females. These data suggest that ZIP9 might be effectively targeted in melanoma and other cancers by repurposing androgen receptor inhibitors that are currently approved only for prostate cancer. SignificanceMelanoma outcomes are worse in males than in females. Some of this difference is driven by testosterone signaling through ZIP9, a nonclassical testosterone receptor. Drugs that target AR can be repurposed to block ZIP9, and inhibit melanoma in males.

cancer biology↗

bioRxiv2017

Non-classical estrogen signaling inhibits melanoma and improves response to PD-1 blockade

Female sex and pregnancy are associated with reduced risk of melanoma and improved stage specific survival; however, the mechanism underlying this apparent clinical benefit is unknown. We previously discovered that pregnancy-associated 17{beta}-estradiol drives melanocyte differentiation by activating the nonclassical G-protein coupled estrogen receptor (GPER). Here, we show that pregnancy inhibits melanoma, and that transient GPER activation induces long-term changes in melanocytes, which are associated with increased cellular differentiation and resistance to melanoma. A selective GPER agonist induced c-Myc protein degradation, slowed tumor growth, and inhibited expression of immune suppressive proteins including PD-L1, suggesting that GPER signaling may render melanoma cells more vulnerable to immunotherapy. Systemically delivered GPER agonist was well tolerated, and cooperated synergistically with PD-1 blockade in melanoma-bearing mice to dramatically extend survival. These results thus define GPER as a target for differentiation-based melanoma therapy.\n\nSignificanceImmune checkpoint inhibitors including PD-1 induce durable remissions in only 30% of patients with advanced melanoma. This work demonstrates that PD-1 efficacy is significantly improved by systemic delivery of a selective agonist of the nonclassical estrogen receptor, GPER, which drives melanoma differentiation and renders tumors more vulnerable to the immune system.

cancer biology↗