Ma, Xiaoyu

BACKGROUND: Although diabetes is a known driver of heart failure with preserved ejection fraction, whether antecedent hyperinsulinemia drives preclinical diastolic dysfunction (DD) progression before overt hyperglycemia remains unknown. Therefore, we investigated whether elevated endogenous insulin and insulin resistance independently predict longitudinal DD progression and adverse cardiovascular outcomes. METHODS: In a community-based cohort study, we evaluated 1191 participants from the Olmsted County Heart Function Study (median age, 58.7 [interquartile range, 52.4–66.6 years]) who underwent echocardiography at baseline and after 4 years. Fasting insulin and homeostatic model assessment of insulin resistance were assessed. The primary end point was DD progression. Secondary outcomes (mortality, heart failure) were assessed in 2030 participants followed for a median of 10.97 (95% CI, 10.90–11.05) years for heart failure and a median of 18.1 (95% CI, 18.0–18.2) years for mortality. RESULTS: DD progression occurred in 7.5% of participants. Baseline fasting insulin and homeostatic model assessment of insulin resistance strongly predicted progression ( P <0.001). In multivariable analysis, every 1-SD increase in log-transformed insulin was associated with 65% increased odds of progression (odds ratio, 1.65 [95% CI, 1.33–2.07]; P <0.001), adjusting for age, creatinine, and NT-proBNP (N-terminal pro-B-type natriuretic peptide). Similar results were observed for homeostatic model assessment of insulin resistance (odds ratio, 1.66 [95% CI, 1.34–2.08]; P <0.001). In secondary analyses, elevated insulin independently predicted all-cause (hazard ratio, 1.11 per 1-SD [95% CI, 1.02–1.21]) and cardiovascular mortality (hazard ratio, 1.16 [95% CI, 1.02–1.33]). Homeostatic model assessment of insulin resistance was similarly predictive of all-cause (hazard ratio, 1.11 [95% CI, 1.03–1.20]) and cardiovascular mortality (hazard ratio, 1.16 [95% CI, 1.02–1.32]). CONCLUSIONS: Elevated endogenous insulin and insulin resistance are predictors of progressive DD and long-term mortality, even after accounting for body mass index. Metabolic dysregulation may drive myocardial stiffening before diabetes onset, identifying a potential early therapeutic window for heart failure with preserved ejection fraction prevention.

Gross anatomy is now delivered in curricula that are increasingly compressed and integrated with other areas of medical training. At the same time, digital resources and physical models have become more common as supplementary tools in anatomy education. These shifts have renewed interest in the distinctive educational value of donor-based learning and in how preservation methods should be aligned with clinically meaningful learning objectives. This narrative review examines the use of fresh human donor tissue in anatomy teaching and clinically oriented procedural training. It focuses on unembalmed, non-fixed, and fresh-frozen tissue, while soft-preserved tissue is considered mainly as contextual and comparative evidence. Literature searches were conducted in MEDLINE, Scopus, Web of Science, and ERIC databases for English-language human studies published from 2015 through early 2026, with backward citation to identify older landmark comparator papers. Because the preservation-explicit educational literature was limited and heterogenous, findings were synthesized narratively. Across the included literature, fresh tissue appears most educationally valuable when learning objectives depend on functional tissue behavior, including tissue palpation, percussion, tissue-plane recognition, ultrasound-guided anatomy, or realistic procedural handling. Available studies suggest benefits in selected knowledge and performance outcomes, especially in clinically oriented examination and postgraduate refresher courses. Comparator evidence indicates that soft-preserved tissue may provide a pragmatic alternative when programs need repeated access or broader curricular integration while still preserving more realistic handling than formal fixed donors. Formalin fixed tissue remains useful for durable structural teaching despite reduced functional realism. Overall, preservation methods should be treated as a curricular design decision rather than a neutral technical detail. Fresh tissue therefore has a defensible place in competency-based anatomy education when used selectively for tasks requiring high functional fidelity, although stronger evidence for long-term clinical transfer remains limited.

Background: Diabetic cardiomyopathy is a common complication of diabetes, which can progress to symptomatic heart failure. Current conventional medical therapy does not reverse the deleterious features of diabetic cardiomyopathy. The natriuretic peptide-cGMP system has been proven to provide a cardioprotective role in diabetic rats. Therefore, we developed CRRL094, a n bispecific peptide that simultaneously activates the natriuretic peptide system and glucagon-like peptide-1 (GLP-1) receptor. In this study, we aimed to characterize the cardioprotective role of CRRL094 and elucidate its downstream molecular mechanisms. Methods: In vitro, human cardiomyocytes (HCMs) were pretreated with PBS or CRRL094 (5 µM) for 6 hours, then exposed to high glucose treatment (HGT, 25 mM) for 48 hours. HCM hypertrophy was determined by assessing mRNA levels of hypertrophic gene markers (NPPA and NPPB) using real-time PCR. Lipid droplet staining was performed using BODIPY 493/503 dye and fluorescence images were analyzed. The protein levels of CIDEC (lipid droplet-related gene) and phosphorylation-AMPK and total AMPK (a key regulator of lipid metabolism) were analyzed by Western blot. In vivo, a type 2 diabetes (DM2) rat model was established by low-dose intraperitoneal Streptozotocin (STZ) injection and a high-fat diet in Wistar rats (male, 4- to 6-week-old). Diabetes was confirmed by fasting blood glucose > 350 mg/dL. Rats were then allocated to two groups: saline-treated controls (n=6) or CRRL094-treated (30 pmol/kg/min; n=6), with treatment delivered via osmotic pumps for 28 days. Heart tissues were collected and analyzed. Results: HGT in HCMs significantly increased the mRNA levels of NPPA and NPPB, whereas CRRL094 significantly attenuated markers of hypertrophy. Further, HGT increased lipid accumulation in HCMs, which was decreased with CRRL094 treatment. Moreover, CRRL094 increased p-AMPK protein levels and decreased CIDEC protein levels in HCMs under HGT. In a DM2 rat model, chronic CRRL094 therapy was associated with suppression of NPPA and NPPB, downregulation of CIDEC, and upregulation of p-AMPK expression in the heart tissue. Conclusion: CRRL094 protects against HGT-induced hypertrophy and inhibits lipid accumulation through regulating the AMPK/CIDEC pathway in vitro and in vivo . These findings support CRRL094 as a novel therapeutic candidate to prevent diabetic cardiomyopathy.

Introduction: Diabetes mellitus (DM) is strongly associated with metabolic and cardiorenal derangements. Natriuretic peptides (NPs), and glucagon-like peptide 1 receptor agonists (GLP-1 RA) have well-established cardiometabolic and cardiorenal protective effects. We developed a novel bispecific biologic, CRRL 101, which agonizes guanylyl cyclase A (GCA) NP receptors and GLP-1 receptors. In this study, we sought to evaluate the in vitro effects and in vivo impact of CRRL 101 in a DM rat model. Methods: In vitro experiments evaluated the impact of CRRL 101 treatment of GCA receptor transfected human embryonic kidney (HEK) cells and INS-1 rat pancreatic beta cells. In vivo experiments were conducted by inducing DM in Wistar rats (male, 6-8-week-old) by intraperitoneal Streptozotocin (STZ) injection (65 mg/kg). One week after STZ injection, DM was confirmed (fasting blood glucose > 350 mg/dL). Rats were then divided into 3 groups: saline control (n=6), 1 pmol/kg/min CRRL-101 (“1pmol” n= 4), and 10 pmol/kg/min CRRL-101 (“10 pmol” n=5). Treatment was infused for 120 min after which rat blood and urine were collected. Data were analyzed using GraphPad Prism 10.0.0. Results: In vitro, there was a marked increase in cyclic GMP (cGMP) levels (pmol/mL) in HEK treated with 10 -6 M CRRL 101 (mean difference ± SEM:1.603 ± 0.29 p = 0.0048). In INS-1 cells treated with CRRL 101 at 10 -6 M in a 20 mM glucose medium, cAMP levels (pmol/mL) markedly increased (16.7 ± 1.47 vs 23.19 ± 1.51 p=0.0036) and insulin levels (ng/mL) doubled (4.4 ng/mL ± 0.44 vs 9.5 ng/mL ± 0.34 in 20 mM glucose p < 0.0001). Similar increases were observed at lower doses (10 -7 M, 10 -8 M) of CRRL 101. In vivo , after 120 minutes of treatment, mean plasma cGMP levels were 6.5x greater in both groups (mean difference± SEM) (1pmol: 38.89 ± 7.93, p = 0.016; 10pmol: 39.40 ± 4.84 p=0.001). Plasma insulin (ng/mL) more than doubled with both doses (1pmol: 0.39 ± 0.148, p = 0.039; 10 pmol: 0.198 ± 0.051, p = 0.004) with no significant increase with placebo ( 0.03 ± 0.08, p = 0.67). Rate of natriuresis (mEq/min) more than doubled with peptide administration vs placebo (1 pmol: 0.36 ± 0.093 p = 0.014; 10 pmol: 0.38 ± 0.13, p = 0.034). Conclusions: Our novel bispecific biologic, CRRL 101, activates GC-A, increasing plasma cGMP and inducing natriuresis, and stimulates GLP-1R, raising cAMP and plasma insulin. Chronic administration studies to eludicate its therapeutic efficacy are warranted.

BACKGROUND: Cardiomyocyte oxidative stress significantly contributes to the progression of hypertension-induced heart failure, highlighting the need for targeted therapies. We developed a novel peptide, NPA7, that coactivates the GC-A (guanylyl cyclase A)/cGMP and MasR (Mas receptor)/cAMP pathway. This study aimed to test NPA7’s ability to inhibit oxidative stress by modulating the p62 (Sequestosome 1)-KEAP1 (Kelch-like ECH-associated protein 1)-NRF2 (nuclear factor erythroid 2-related factor 2) pathway in human cardiomyocytes (HCMs) and a rat model of hypertension. METHODS: Oxidative stress was induced in HCMs using H 2 O 2 with phosphate-buffered saline or NPA7 treatment. Intracellular reactive oxygen species levels were assessed via dihydroethidium staining. Western blotting analysis measured p62, KEAP1, and NRF2 protein levels, while GSH/GSSG (glutathione/glutathione disulfide) ratios and antioxidant gene expression were analyzed. HCMs were transfected with small interfering RNA targeting GC-A, MasR, or p62 before NPA7 and H 2 O 2 treatment. In vivo, spontaneously hypertensive rats received saline or NPA7, with normotensive Wistar Kyoto rats as control and cardiac oxidative stress, KEAP1 protein levels, NOX2 (NADPH oxidase 2), and p67 (NADPH oxidase subunit p67-phox) mRNA levels were measured. RESULTS: NPA7 reduced H 2 O 2 -induced reactive oxygen species levels and increased GSH/GSSG ratio in HCMs. Silencing GC-A (guanylyl cyclase A receptor) and MasR (Mas receptor) reversed NPA7’s effects. NPA7 activated the KEAP1-NRF2 pathway, enhancing NRF2’s antioxidant target gene expression. In p62 knockdown HCMs, NPA7-induced KEAP1 degradation and NRF2 activation were diminished. Reactive oxygen species levels were elevated in spontaneously hypertensive rat versusWistar Kyoto rats’ hearts, however, NPA7 treatment reduced myocardial reactive oxygen species, suppressed KEAP1 protein, and decreased NOX2 and p67 mRNA levels. CONCLUSIONS: NPA7 exhibits antioxidant properties in HCMs and spontaneously hypertensive rat hearts by targeting GC-A and MasR through the p62-KEAP1-NRF2 pathway, supporting a novel therapeutic approach against cardiovascular disease–related oxidative stress.

Background: Tyrosine kinase inhibitors (TKIs), such as sunitinib, are highly effective in treating cancers. However, they have severe cardiovascular (CV) side effects that include cardiotoxicity via cardiomyocyte injury and death resulting in myocardial dysfunction. There are no FDA-approved drugs to prevent or treat cardiotoxicity, which have been linked mechanistically to mitochondrial dysfunction and oxidative stress, highlighting the need for new therapeutics. Two recognized CV protective pathways are the particulate guanylyl cyclase A receptor (GC-A)/cGMP and the Mas receptor (MasR)/cAMP pathways. We recently engineered NPA7 a novel peptide that activates both pathways. Aim: Here we investigated NPA7’s ability to protect against sunitinib-induced cardiotoxicity in human cardiomyocytes (HCMs) and defined its role on mitochondrial function. Methods: HCMs were treated with DMSO or sunitinib (10 µM) together with PBS or NPA7 (10 µM). Intracellular reactive oxygen species (ROS) was assessed by DHE staining. CCK8 assay was performed to measure cell viability. TOM20 staining were performed by immunofluorescence and the mitochondrial length was analyzed. The protein levels of mitochondrial dynamics markers (fission: MFF, Fis1; fusion: OPA1 and MFN1) proteins were measured by western blot. Cell surface area was assessed by phalloidin staining with mRNA levels of hypertrophic gene markers (NPPA and MYH7) in HCMs using real-time PCR. Results: Sunitinib increased DHE staining and intracellular ROS in HCMs, which was decreased with NPA7 treatment. NPA7 enhanced HCM cell viability in the presence of sunitinib. TOM20 staining showed a marked reduction in mitochondrial length in sunitinib group, compared to DMSO group, whereas NPA7 treatment rescued mitochondria length (DMSO= 6.15 ± 0.94 μm, Sunitinib= 2.42 ± 0.63 μm, NPA7= 5.4 ± 1.19 μm; P < 0.05). Moreover, NPA7 inhibited mitochondrial fission protein levels (MFF and Fis1) and increased mitochondrial fusion protein levels (OPA1, MFN1) in HCMs treated with sunitinib. Sunitinib treatment notably increased HCM cell surface area and hypertrophic gene markers (NPPA and MYH7), whereas NPA7 abolished these markers of hypertrophy. Conclusions: We report, for the first time, that NPA7 protects against sunitinib induced oxidative stress, mitochondrial fragmentation, hypertrophy and cell death in HCMs. These data support a novel therapeutic approach against TKI-induced cardiotoxicity with NPA7 to which no therapies exist.

Heterotopic ossification (HO), defined as the formation of extraskeletal bone in muscle and soft tissues, is a diverse pathological process caused by either genetic mutations or inciting trauma. Fibrodysplasia ossificans progressiva (FOP) is a genetic form of HO caused by mutations in the bone morphogenetic protein (BMP) type I receptor gene activin A receptor type 1 ( ACVR1 ). These mutations make ACVR1 hypersensitive to BMP and responsive to activin A. Hedgehog (Hh) signaling also contributes to HO development. However, the exact pathophysiology of how skeletogenic cells contribute to endochondral ossification in FOP remains unknown. Here, we showed that the wild-type or FOP-mutant ACVR1 localized in the cilia of stem cells from human exfoliated deciduous teeth with key FOP signaling components, including activin A receptor type 2A/2B, SMAD family member 1/5, and FK506-binding protein 12kD. Cilia suppression by deletion of intraflagellar transport 88 or ADP ribosylation factor like GTPase 3 effectively inhibited pathological BMP and Hh signaling, subdued aberrant chondro-osteogenic differentiation in primary mouse or human FOP cells, and diminished in vivo extraskeletal ossification in Acvr1 Q207D , Sox2-Cre ; Acvr1 R206H/+ FOP mice and in burn tenotomy–treated wild-type mice. Our results provide a rationale for early and localized suppression of cilia in affected tissues after injury as a therapeutic strategy against either genetic or acquired HO.

Abstract Myocardial fibrosis is a pathological hallmark of cardiovascular disease (CVD), and excessive fibrosis can lead to new-onset heart failure and increased mortality. Currently, pharmacological therapies for myocardial fibrosis are limited, highlighting the need for novel therapeutic approaches. The particulate guanylyl cyclase B (GC-B) receptor possesses beneficial antifibrotic actions through the binding of its natural ligand C-type natriuretic peptide (CNP) and the generation of the intracellular second messenger, cyclic guanosine 3′,5′-monophosphate (cGMP). These actions include the suppression of fibroblast proliferation and reduction in collagen synthesis. With its abundant expression on fibroblasts, the GC-B receptor has emerged as a key molecular target for innovative CVD therapeutics. However, small molecules that can bind and potentiate the GC-B/cGMP pathway have yet to be discovered. From a cell-based high-throughput screening initiative of the NIH Molecular Libraries Small Molecule Repository and hit-to-lead evolution based on a series of structure–activity relationships, we report the successful discovery of MCUF-42, a GC-B-targeted small molecule that acts as a positive allosteric modulator (PAM). Studies herein support MCUF-42's ability to enhance the binding affinity between GC-B and CNP. Moreover, MCUF-42 potentiated cGMP levels induced by CNP in human cardiac fibroblasts (HCFs) and notably also enhanced the inhibitory effect of CNP on HCF proliferation. Together, our findings highlight that MCUF-42 is a small molecule that can modulate the GC-B/cGMP signaling pathway, potentially enhancing the antifibrotic actions of CNP. Thus, these data underscore the continued development of GC-B small molecule PAMs as a novel therapeutic strategy for targeting cardiac fibrosis and CVD.

Introduction: Excess cardiomyocyte oxidative stress is a major metabolic abnormality in HTN and its progression to HF. Thus, therapies that reduce oxidative stress in the heart may lead to a reduction in CVD related adverse outcomes such as HF and death. Recently, we bioengineered a bispecific peptide NPA7 that co-activates the protective GC-A/cGMP and MasR/cAMP pathways. Previously we showed that NPA7 possesses cardiorenal protective properties. However, the antioxidant effects of NPA7 within the heart is unknown. Hypothesis: NPA7 protects human cardiomyocytes against oxidative stress through the GC-A/Mas Receptor-KEAP1-NRF2 pathway. Methods: HCMs were pretreated with PBS or NPA7 (10 uM) followed by 400 uM hydrogen peroxide (H2O2) to induce oxidative stress. Intracellular ROS was measured by dihydroethidium (DHE) staining and protein levels of KEAP1 and NRF2 via western blot. The ratio of GSH/GSSG were determined by using commercial kit. mRNA levels of G6PD, GCLC, GCLM and GSS in HCMs, which represents antioxidant capacity, were determined by real-time PCR. For knockdown experiments, HCMs were transfected with the siRNA target GC-A and MasR for 24 h and then treated with NPA7 and H2O2 for another 20 h. Results: H2O2 increased DHE staining level, which indicated elevated intracellular ROS levels within HCMs. Notably, treatment with NPA7 decreased DHE level and increased the ratio of GSH/GSSG in HCMs with H2O2. Furthermore, NPA7 significantly increased the mRNA level of NRF2 target genes (G6PD, GCLC, GCLM, GSS) through NRF2 activation and KEAP1 degradation, indicating that NPA7 activates KEAP1-NRF2 pathway, the upstream pathway that regulate antioxidant gene expression, in HCMs. Moreover, these effects were eliminated if GC-A and MasR were silenced by siRNA, thus supporting the protective antioxidant role of both GC-A and MasR. Conclusions: The present study establishes an antioxidant action of NPA7, a novel bispecific designer peptide, on H2O2-induced oxidative stress by the dual targeting of GC-A and MasR through the KEAP1-NRF2 signaling pathway in HCMs. These results advance NPA7 as an innovative therapeutic strategy targeting oxidative stress related to CVD.

Introduction: Hypertension (HTN) represents one of the greatest burdens in human health and is associated with increased morbidity and mortality. Despite the availability of several antihypertensive drugs, most patients have suboptimal blood pressure (BP) control, thus underscoring the need for new therapeutic drugs. The natriuretic peptide receptor A (NPRA) possesses potent vasodilating, natriuretic and diuretic actions via activation by ANP or BNP and generation of its second messenger, cGMP. Recently, we reported the discovery of a small molecule positive allosteric modulator (PAM) for NPRA, MCUF-651, which enhances the ANP/BNP/NPRA/cGMP pathway (PNAS,2021). To date, the in vivo actions of MCUF-651 remains unknown. Here we tested the hypothesis that MCUF-651 would have BP lowering and renal enhancing properties in experimental HTN. Methods: A single IV bolus of MCUF-651 (10mg/kg; n=4) or vehicle (V; n=5) was injected into anesthetized spontaneous hypertensive rats (SHRs). Plasma and urinary cGMP (PcGMP and UcGMP), mean arterial pressure (MAP) and urinary volume (UV) and sodium (UNa) excretion were assessed at baseline (BL) and over 60-mins post-bolus. Results: In SHRs, PcGMP and UcGMP were significantly elevated with MCUF-651 compared to the vehicle group (ΔPcGMP MCUF-651: 16±5, ΔPcGMP V: -2±3, pmol/mL; P =0.003; ΔUcGMP MCUF-651: 78±29, ΔUcGMP V: 30±8, pmol/min, P =0.01), thus supporting NPRA target engagement. Notably, the elevations in cGMP with MCUF-651 were associated with a significant reduction in MAP at 15-mins post bolus compared to vehicle (ΔMAP MCUF-651: -29±14, ΔMAP V: -6±2 mmHg; P =0.04) and this MAP reduction was sustained over 60 mins. Further, UV and UNa excretion were significantly increased, from BL, with MCUF-651 (BL UV: 6 ± 2, 60 mins post bolus UV: 56± 18 μL/min, P <0.001; BL UNa: 1±0.2, 60 mins post bolus UNa: 8±2 μmol/min, P <0.001). Conclusions: We report for the first time that MCUF-651, a novel NPRA small molecule PAM, engages NPRA, increases cGMP and reduces MAP while enhancing sodium and water excretion in experimental HTN. These findings support the development of MCUF-651 as a potential new therapeutic modality to optimize BP lowering goals and reduce adverse outcomes in human HTN.