Correction: Pannala et al. High-Throughput Transcriptomics Differentiates Toxic versus Non-Toxic Chemical Exposures Using a Rat Liver Model. Int. J. Mol. Sci. 2023, 24, 17425.

In the original publication [...].

Exposure to PFAS chemicals induces sex-dependent alterations in key rate-limiting steps of lipid metabolism in liver steatosis.

Toxicants with the potential to bioaccumulate in humans and animals have long been a cause for concern, particularly due to their association with multiple diseases and organ injuries. Per- and polyfluoro alkyl substances (PFAS) and polycyclic aromatic hydrocarbons (PAH) are two such classes of chemicals that bioaccumulate and have been associated with steatosis in the liver. Although PFAS and PAH are classified as chemicals of concern, their molecular mechanisms of toxicity remain to be explored in detail. In this study, we aimed to identify potential mechanisms by which an acute exposure to PFAS and PAH chemicals can induce lipid accumulation and whether the responses depend on chemical class, dose, and sex. To this end, we analyzed mechanisms beginning with the binding of the chemical to a molecular initiating event (MIE) and the consequent transcriptomic alterations. We collated potential MIEs using predictions from our previously developed ToxProfiler tool and from published steatosis adverse outcome pathways. Most of the MIEs are transcription factors, and we collected their target genes by mining the TRRUST database. To analyze the effects of PFAS and PAH on the steatosis mechanisms, we performed a computational MIE-target gene analysis on high-throughput transcriptomic measurements of liver tissue from male and female rats exposed to either a PFAS or PAH. The results showed peroxisome proliferator-activated receptor (PPAR)-α targets to be the most dysregulated, with most of the genes being upregulated. Furthermore, PFAS exposure disrupted several lipid metabolism genes, including upregulation of fatty acid oxidation genes (Acadm, Acox1, Cpt2, Cyp4a1-3) and downregulation of lipid transport genes (Apoa1, Apoa5, Pltp). We also identified multiple genes with sex-specific behavior. Notably, the rate-limiting genes of gluconeogenesis (Pck1) and bile acid synthesis (Cyp7a1) were specifically downregulated in male rats compared to female rats, while the rate-limiting gene of lipid synthesis (Scd) showed a PFAS-specific upregulation. The results suggest that the PPAR signaling pathway plays a major role in PFAS-induced lipid accumulation in rats. Together, these results show that PFAS exposure induces a sex-specific multi-factorial mechanism involving rate-limiting genes of gluconeogenesis and bile acid synthesis that could lead to activation of an adverse outcome pathway for steatosis.

The Impact of Metabolic Bariatric Surgery on Cardiovascular Diseases in Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease.

PURPOSE: There is a strong association between metabolic dysfunction-associated steatotic liver disease (MASLD) and obesity which are both important risk factors for cardiovascular diseases (CVDs). The current study aimed to assess the association of MBS with different CVDs in patients with MASLD. MATERIALS AND METHODS: The National Inpatient Sample (NIS) database from 2016 to 2020 were analyzed by using ICD-10 codes. A propensity score matching in a 1:1 ratio was done to match the MBS and non-MBS groups. RESULTS: After weighted analysis, 1,124,155 and 68,215 patients were included in non-MBS and MBS groups, respectively. MBS was associated with significantly lower risk of hospitalization for coronary artery disease (OR 0.633 (0.569-0.703), p value < 0.001), acute myocardial infarction (OR 0.606 (0.523-0.701), p value < 0.001), percutaneous coronary intervention (OR 0.578 (0.489-0.682), p value < 0.001), and thrombolysis (OR 0.765 (0.589-0.993), p value = 0.044) compared to the non-MBS group in patients with MASLD. Furthermore, MBS was associated with 52% reduced risk of hospitalization for hemorrhagic stroke in patients with MASLD (OR 0.481, 95% CI 0.337-0.686, p value < 0.001). However, ischemic stroke was not significant between the two groups (OR 1.108 (0.905-1.356), p value = 0.322). In addition, MBS was associated with 63% and 60% reduced risk of hospitalization for heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF) in patients with MASLD (OR 0.373, 95% CI 0.300-0.465 and OR 0.405, 95% CI 0.325-0.504, p value < 0.001 for both), respectively. CONCLUSION: The current study showed that MBS is significantly associated with a reduced risk of hospitalization for CVD in patients with MASLD.

The open abdomen in mesenteric ischemia: A tool for patients undergoing revascularization.

BACKGROUND: We examined outcomes in Acute Mesenteric Ischemia (AMI) with the hypothesis that Open Abdomen (OA) is associated with decreased mortality. METHODS: We performed a cohort study reviewing NSQIP emergency laparotomy patients, 2016-2020, with a postoperative diagnosis of mesenteric ischemia. OA was defined using flags for patients without fascial closure. Logistic regression was used with outcomes of 30-day mortality and several secondary outcomes. RESULTS: Out of 5514 cases, 4624 (83.9%) underwent resection and 387 (7.0%) underwent revascularization. The OA rate was 32.6%. 10.8% of patients who were closed required reoperation. After adjustment for demographics, transfer status, comorbidities, preoperative variables including creatinine, white blood cell count, and anemia, as well as operative time, OA was associated with OR 1.58 for mortality (95% CI [1.38, 1.81], p < 0.001). Among revascularizations, there was no such association (p = 0.528). OA was associated with ventilator support >48 h (OR 4.04, 95% CI [3.55, 4.62], and p < 0.001). CONCLUSION: OA in AMI was associated with increased mortality and prolonged ventilation. This is not so in revascularization patients, and 1 in 10 patients who underwent primary closure required reoperation. OA should be considered in specific cases of AMI. LEVEL OF EVIDENCE: Retrospective cohort, Level III.

Probing Liver Injuries Induced by Thioacetamide in Human In Vitro Pooled Hepatocyte Experiments.

Animal studies are typically utilized to understand the complex mechanisms associated with toxicant-induced hepatotoxicity. Among the alternative approaches to animal studies, in vitro pooled human hepatocytes have the potential to capture population variability. Here, we examined the effect of the hepatotoxicant thioacetamide on pooled human hepatocytes, divided into five lots, obtained from forty diverse donors. For 24 h, pooled human hepatocytes were exposed to vehicle, 1.33 mM (low dose), and 12 mM (high dose) thioacetamide, followed by RNA-seq analysis. We assessed gene expression variability using heat maps, correlation plots, and statistical variance. We used KEGG pathways and co-expression modules to identify underlying physiological processes/pathways. The co-expression module analysis showed that the majority of the lots exhibited activation for the bile duct proliferation module. Despite lot-to-lot variability, we identified a set of common differentially expressed genes across the lots with similarities in their response to amino acid, lipid, and carbohydrate metabolism. We also examined efflux transporters and found larger lot-to-lot variability in their expression patterns, indicating a potential for alteration in toxicant bioavailability within the cells, which could in turn affect the gene expression patterns between the lots. Overall, our analysis highlights the challenges in using pooled hepatocytes to understand mechanisms of toxicity.

Structural and functional interactions between the EF hand domain and S2-S3 loop in the type-1 ryanodine receptor ion channel.

Previous cryo-electron micrographs suggested that the skeletal muscle Ca2+ release channel, ryanodine receptor (RyR)1, is regulated by intricate interactions between the EF hand Ca2+ binding domain and the cytosolic loop (S2-S3 loop). However, the precise molecular details of these interactions and functional consequences of the interactions remain elusive. Here, we used molecular dynamics simulations to explore the specific amino acid pairs involved in hydrogen bond interactions within the EF hand-S2-S3 loop interface. Our simulations unveiled two key interactions: (1) K4101 (EF hand) with D4730 (S2-S3 loop) and (2) E4075, Q4078, and D4079 (EF hand) with R4736 (S2-S3 loop). To probe the functional significance of these interactions, we constructed mutant RyR1 complementary DNAs and expressed them in HEK293 cells for [3H]ryanodine binding assays. Our results demonstrated that mutations in the EF hand, specifically K4101E and K4101M, resulted in reduced affinities for Ca2+/Mg2+-dependent inhibitions. Interestingly, the K4101E mutation increased the affinity for Ca2+-dependent activation. Conversely, mutations in the S2-S3 loop, D4730K and D4730N, did not significantly change the affinities for Ca2+/Mg2+-dependent inhibitions. Our previous finding that skeletal disease-associated RyR1 mutations, R4736Q and R4736W, impaired Ca2+-dependent inhibition, is consistent with the current results. In silico mutagenesis analysis aligned with our functional data, indicating altered hydrogen bonding patterns upon mutations. Taken together, our findings emphasize the critical role of the EF hand-S2-S3 loop interaction in Ca2+/Mg2+-dependent inhibition of RyR1 and provide insights into potential therapeutic strategies targeting this domain interaction for the treatment of skeletal myopathies.

High-Throughput Transcriptomics Differentiates Toxic versus Non-Toxic Chemical Exposures Using a Rat Liver Model.

To address the challenge of limited throughput with traditional toxicity testing, a newly developed high-throughput transcriptomics (HTT) platform, together with a 5-day in vivo rat model, offers an alternative approach to estimate chemical exposures and provide reasonable estimates of toxicological endpoints. This study contains an HTT analysis of 18 environmental chemicals with known liver toxicity. They were evaluated using male Sprague Dawley rats exposed to various concentrations daily for five consecutive days via oral gavage, with data collected on the sixth day. Here, we further explored the 5-day rat model to identify potential gene signatures that can differentiate between toxic and non-toxic liver responses and provide us with a potential histopathological endpoint of chemical exposure. We identified a distinct gene expression pattern that differentiated non-hepatotoxic compounds from hepatotoxic compounds in a dose-dependent manner, and an analysis of the significantly altered common genes indicated that toxic chemicals predominantly upregulated most of the genes and several pathways in amino acid and lipid metabolism. Finally, our liver injury module analysis revealed that several liver-toxic compounds showed similarities in the key injury phenotypes of cellular inflammation and proliferation, indicating potential molecular initiating processes that may lead to a specific end-stage liver disease.

Molecular basis and cellular functions of vinculin-actin directional catch bonding.

The ability of cells and tissues to respond differentially to mechanical forces applied in distinct directions is mediated by the ability of load-bearing proteins to preferentially maintain physical linkages in certain directions. However, the molecular basis and biological consequences of directional force-sensitive binding remain unclear. Vinculin (Vcn) is a load-bearing linker protein that exhibits directional catch bonding due to interactions between the Vcn tail domain (Vt) and filamentous (F)-actin. We developed a computational approach to predict Vcn residues involved in directional catch bonding and produced a set of associated Vcn variants with unaltered Vt structure, actin binding, or phospholipid interactions. Incorporation of the variants did not affect Vcn activation but reduced Vcn loading and altered exchange dynamics, consistent with the loss of directional catch bonding. Expression of Vcn variants perturbed the coordination of subcellular structures and cell migration, establishing key cellular functions for Vcn directional catch bonding.

Cholesterol crystals induce mechanical trauma, inflammation, and neo-vascularization in solid cancers as in atherosclerosis.

Background and aims: Cancer and atherosclerosis share common risk factors and inflammatory pathways that promote their proliferation via vascular endothelial growth factor (VEGF). Because CCs cause mechanical injury and inflammation in atherosclerosis, we investigated their presence in solid cancers and their activation of IL-1ß, VEGF, CD44, and Ubiquityl-Histone H2B (Ub-H2B), that promote cancer growth. Methods: Tumor specimens from eleven different types of human cancers and atherosclerotic plaques were assessed for CCs, free cholesterol content and IL1-ß by microscopy, immunohistochemistry, and biochemical analysis. Breast and colon cancer cell lines were cultured with and without CCs to select for expression of VEGF, CD44, and Ub-H2B. Western blot and immunofluorescence were performed on cells to assess the effect of CCs on signaling pathways. Results: Cancers displayed higher CC content (+2.29 ± 0.74 vs +1.46 ± 0.84, p < 0.0001), distribution (5.06 ± 3.13 vs 2.86 ± 2.18, p < 0.001) and free cholesterol (3.63 ± 4.02 vs 1.52 ± 0.56 µg/mg, p < 0.01) than cancer free marginal tissues and similarly for atherosclerotic plaques and margins (+2.31 ± 0.51 vs +1.44 ± 0.79, p < 0.02; 14.0 ± 5.74 vs 8.14 ± 5.52, p < 0.03; 0.19 ± 0.14 vs 0.09 ± 0.04 µg/mg, p < 0.02) respectively. Cancers displayed significantly increased expression of IL1-ß compared to marginal tissues. CCs treated cancer cells had increased expression of VEGF, CD44, and Ub-H2B compared to control. By microscopy, CCs were found perforating cancer tumors similar to plaque rupture. Conclusions: These findings suggest that CCs can induce trauma and activate cytokines that enhance cancer growth as in atherosclerosis.

Rapid Pathogen Purge by Photosensitive Arginine-Riboflavin Carbon Dots without Toxicity.

Photo-activatable antipathogenic carbon dots (CDs) were prepared by carbonization of citric acid and arginine (Arg) via 3 min microwave treatment for use in the eradication of common microorganisms. Nitrogen-doped Arg CDs were spherical in shape with a size range of 0.5 to 5 nm. The Arg CDs were modified with fluorescent dyes, such as fluorescein sodium salt (FSS, as Arg-FSS) and riboflavin (RBF, as Arg-RBF), to improve antimicrobial potency by enhancing their application in photodynamic therapy. The modified Arg CDs afforded fluorescence emission properties at 520 nm in the green region in addition to excellent blue fluorescence intensity at 420 nm under 345 nm excitation upon their FSS and RBF conjugation, respectively. Although the cytotoxicity of Arg CDs was decreased for Arg-RBF CDs to 91.2 ± 0.7% cell viability for fibroblasts, the Arg-based CDs could be safely used for intravenous applications at 1000 µg/mL concentration. The Arg CDs showed broad-spectrum antimicrobial activity against common pathogens and the minimum inhibitory concentration of Arg CDs was almost two-fold decreased for the modified forms without UV light. However, faster and more effective antibacterial activity was determined for photosensitive Arg-RBF CDs, with total bacterial eradication upon UV-A light exposure for 30 min.

Bariatric Surgery and Risk of Hospitalization for Gastrointestinal Cancers in the USA: a Propensity Score Matched Analysis of National Inpatient Sample Study.

BACKGROUND: There are some concerns about the higher risk of certain gastrointestinal (GI) cancers in patients with a history of bariatric metabolic surgery (BMS). The current study aimed to investigate the association of BMS with GI cancer hospital admission including esophageal, gastric, colorectal, small intestinal, liver, gallbladder, bile duct, and pancreatic cancers. METHODS: The analysis utilized the US national inpatient sample (NIS) data from 2016 to 2020, employing ICD-10 codes. A propensity score matching in a 3:1 ratio was done to match the BMS and non-BMS groups. RESULTS: A total of 328,369 patients with a history of BMS and 4,989,154 with obesity and without a history of BMS were included in this study. BMS was independently associated with a higher risk of gastric and pancreatic cancers hospital admission (OR: 1.69 (CI 95%: 1.42-2.01) and OR: 1.46 (CI 95%: 1.27-1.68)), respectively. In addition, BMS was independently associated with a lower risk of colorectal and liver cancer hospital admission (OR: 0.57 (CI 95%: 0.52-0.62) and OR: 0.72 (CI 95%: 0.52-0.98)), respectively. Besides, esophageal, gallbladder, bile duct, and small intestinal cancer were not significantly different between the two groups. In patients with GI cancer, although the BMS group had significantly lower total charges and length of hospital stay compared to the non-BMS group, the rate of in-hospital mortality was not significantly different. CONCLUSION: The current study showed that bariatric surgery may be associated with a higher risk of gastric and pancreatic cancer and a lower risk of colorectal and liver cancer hospital admission. Further research is needed to explore this association.

Bariatric Surgery and Cardiovascular Disease Risk in Patients with Pulmonary Hypertension: A Propensity Score Matched Analysis of US National Inpatient Sample.

PURPOSE: Previous research has suggested the ameliorating effect of bariatric surgery (BaS) on patients with pulmonary hypertension (PH), but there is a lack of data on the effect of bariatric surgery on the odds of cardiovascular diseases in PH patients. The current study aims to evaluate the association of BaS and coronary artery diseases (CAD), heart failure with reduced ejection fraction (HFrEF), heart failure with preserved ejection fraction (HFpEF), cardiac valve diseases, cardiac rhythm disorders, acute pulmonary embolism, and in-hospital mortality in patients with PH. METHODS: The national inpatient sample (NIS) data from 2016 to 2019 were analyzed by using ICD-10 codes. A propensity score matching in a 3:1 ratio was performed to match the BaS and non-BaS groups. RESULTS: A total of 3605 patients with a history of BaS and 501419 patients without a history of BaS were included. After propensity matching, BaS was independently associated with a lower CAD hospital admission and a lower rate of in-hospital mortality. On the contrary, BaS was associated with a higher prevalence of atrial fibrillation (AF) and acute pulmonary embolism in patients with PH. HFpEF, HFrEF, other cardiac rhythm disorders, complete heart block, cardiac valve diseases, and ischemic stroke were not significantly different between the two groups in patients with PH. CONCLUSION: BaS is independently associated with a reduced rate of in-hospital mortality and CAD hospital admission in patients with PH. However, the risk of atrial fibrillation and acute pulmonary embolism was higher in these patients.

A stochastic B cell affinity maturation model to characterize mechanisms of protection for tetravalent dengue vaccine constructs.

Dengue annually infects millions of people from a regionally and seasonally varying dengue virus population circulating as four distinct serotypes. Effective protection against dengue infection and disease requires tetravalent vaccine formulations to stimulate a balanced protective immune response to all four serotypes. However, this has been a challenge to achieve, and several clinical trials with different leading vaccine candidates have demonstrated unbalanced replication and interference of interindividual serotype components, leading to low efficacy and enhanced disease severity for dengue-naïve populations. Production of serotype-specific neutralizing antibodies is largely viewed as a correlate of protection against severe dengue disease. However, the underlying mechanisms that lead to these protective immune responses are not clearly elucidated. In this work, using a stochastic model of B cell affinity maturation, we tested different live-attenuated vaccine constructs with varied viral replication rates and contrasted the initiation and progress of adaptive immune responses during tetravalent vaccination and after dengue virus challenge. Comparison of our model simulations across different disease-severity levels suggested that individual production of high levels of serotype-specific antibodies together with a lower cross-reactive antibody are better correlates for protection. Furthermore, evolution of these serotype-specific antibodies was dependent on the percent of viral attenuation in the vaccine, and production of initial B cell and T cell populations pre- and post-secondary dengue infection was crucial in providing protective immunity for dengue-naïve populations. Furthermore, contrasting disease severity with respect to different dengue serotypes, our model simulations showed that tetravalent vaccines fare better against DENV-4 serotype when compared to other serotypes.

Bedside Clinician's Guide to Pulmonary Artery Catheters.

BACKGROUND: Pulmonary artery catheters provide important information about cardiac function, mixed venous oxygenation, and right-sided pressures and potentially provide temporary pacing ability. OBJECTIVE: To provide bedside clinicians with guidance for techniques to insert right heart monitors and devices, describe risk factors for difficult insertion and contraindications to placement, and provide updates on new technologies that may be encountered in the intensive care unit. METHODS: An extensive literature review was performed. Experienced clinicians were asked to identify topics not addressed in the literature. RESULTS: Advanced imaging techniques such as transesophageal echocardiography or fluoroscopy can supplement traditional pressure waveform-guided insertion when needed, and several other techniques can be used to facilitate passage into the pulmonary artery. Caution is warranted when attempting insertion in patients with right-sided masses or preexisting conduction abnormalities. New technologies include a pacing catheter that anchors to the right ventricle and a remote monitoring device that is implanted in the pulmonary artery. DISCUSSION: Bedside clinicians should be aware of risk factors such as atrial fibrillation with dilated atria, decreased ventricular function, pulmonary hypertension, and right-sided structural abnormalities that can make pulmonary artery catheter insertion challenging. Clinicians should be familiar with advanced techniques and imaging options to facilitate placement. CONCLUSION: The overall risk of serious complications with right heart catheter placement and manipulation is low and often outweighed by its benefits, specifically pressure monitoring and pacing.

Vaccines and cardiovascular outcomes: lessons learned from influenza epidemics.

Cardiovascular disease (CVD) is the leading cause of death in the world and is largely preventable. An increasing amount of evidence suggests that annual influenza vaccination reduces CVD-related morbidity and mortality. Despite various clinical guidelines recommending annual influenza vaccination for the general population for influenza-like illness risk reduction, with a particular emphasis on people with CVD, vaccination rates fall consistently below the goal established by the World Health Organization. This review outlines the importance of influenza vaccination, mechanisms of cardiovascular events in influenza, summarizing the available literature on the effects of influenza vaccine in CVD and the benefits of influenza vaccine during the COVID-19 pandemic.

Urolithin A analog inhibits castration-resistant prostate cancer by targeting the androgen receptor and its variant, androgen receptor-variant 7.

We investigated the efficacy of a small molecule ASR-600, an analog of Urolithin A (Uro A), on blocking androgen receptor (AR) and its splice variant AR-variant 7 (AR-V7) signaling in castration-resistant prostate cancer (CRPC). ASR-600 effectively suppressed the growth of AR+ CRPC cells by inhibiting AR and AR-V7 expressions; no effect was seen in AR- CRPC and normal prostate epithelial cells. Biomolecular interaction assays revealed ASR-600 binds to the N-terminal domain of AR, which was further confirmed by immunoblot and subcellular localization studies. Molecular studies suggested that ASR-600 promotes the ubiquitination of AR and AR-V7 resulting in the inhibition of AR signaling. Microsomal and plasma stability studies suggest that ASR-600 is stable, and its oral administration inhibits tumor growth in CRPC xenografted castrated and non-castrated mice. In conclusion, our data suggest that ASR-600 enhances AR ubiquitination in both AR+ and AR-V7 CRPC cells and inhibits their growth in vitro and in vivo models.

Advances in Extracorporeal Support Technologies in Critically Ill Children.

The field of pediatric heart failure is evolving, and the patient population is growing as survival after complex congenital heart surgeries is improving. Mechanical circulatory support and extracorporeal respiratory support in critically ill children has progressed to a mainstay rescue modality in pediatric intensive care medicine. The need for mechanical circulatory support is growing, since the number of organ donors does not meet the necessity. This article aims to review the current state of available mechanical circulatory and respiratory support systems in acute care pediatrics, with an emphasis on the literature discussing the challenges associated with these complex support modalities.

Current State and Opportunities with Long-acting Injectables: Industry Perspectives from the Innovation and Quality Consortium "Long-Acting Injectables" Working Group.

Long-acting injectable (LAI) formulations can provide several advantages over the more traditional oral formulation as drug product opportunities. LAI formulations can achieve sustained drug release for extended periods of time, which results in less frequent dosing requirements leading to higher patient adherence and more optimal therapeutic outcomes. This review article will provide an industry perspective on the development and associated challenges of long-acting injectable formulations. The LAIs described herein include polymer-based formulations, oil-based formulations, and crystalline drug suspensions. The review discusses manufacturing processes, including quality controls, considerations of the Active Pharmaceutical Ingredient (API), biopharmaceutical properties and clinical requirements pertaining to LAI technology selection, and characterization of LAIs through in vitro, in vivo and in silico approaches. Lastly, the article includes a discussion around the current lack of suitable compendial and biorelevant in vitro models for the evaluation of LAIs and its subsequent impact on LAI product development and approval.