Impact of Bariatric Surgery on Treatment Burden and Progression of Diabetic Retinopathy.

Purpose: To assess the severity, progression, and treatment burden of diabetic retinopathy (DR) in patients after bariatric surgery compared with controls. Methods: A retrospective cohort study was performed of patients with type 2 diabetes and DR seen at the Duke Eye Center between 2014 and 2023. Clinical data included hemoglobin A1c (HbA1c), diagnostic stage of DR, diabetic macular edema (DME) or vitreous hemorrhage (VH), visual acuity (VA), and treatment burden at baseline and follow-up. Generalized estimating equation analysis was used to account for the correlation between 2 eyes of the same patient. Results: Sixteen patients who had bariatric surgery were matched by age, sex, and duration of diabetes with 60 control patients managed medically during the same time period. The HbA1c level, severity of DR, presence of DME or VH, VA, and treatment burden were not significantly different (all P > .05) at the baseline examination. On average, patients were followed for 6 years. The HbA1c level at the follow-up was significantly lower in the bariatric surgery group (6.4% vs 8.5%; P < .001). At the follow-up, the treatment burden was reduced in the bariatric surgery group compared with the control group (P = .04). There was a clear trend toward reduced progression of DR and treatment burden in the bariatric surgery group over the follow-up. Conclusions: Bariatric surgery may improve glycemic control, stabilize DR progression, and reduce the treatment burden, which may have a significant impact on quality of life for patients with DR.

Nicotine inhalant via E-cigarette facilitates sensorimotor function recovery by upregulating neuronal BDNF-TrkB signalling in traumatic brain injury.

BACKGROUND AND PURPOSE: Traumatic brain injury (TBI) causes lifelong physical and psychological dysfunction in affected individuals. The current study investigated the effects of chronic nicotine exposure via E-cigarettes (E-cig) (vaping) on TBI-associated behavioural and biochemical changes. EXPERIMENTAL APPROACH: Adult C57/BL6J male mice were subjected to controlled cortical impact (CCI) followed by daily exposure to E-cig vapour for 6 weeks. Sensorimotor functions, locomotion, and sociability were subsequently evaluated by nesting, open field, and social approach tests, respectively. Immunoblots were conducted to examine the expression of mature brain-derived neurotrophic factor (mBDNF) and associated downstream proteins (p-Erk, p-Akt). Histological analyses were performed to evaluate neuronal survival and neuroinflammation. KEY RESULTS: Post-injury chronic nicotine exposure significantly improved nesting performance in CCI mice. Histological analysis revealed increased survival of cortical neurons in the perilesion cortex with chronic nicotine exposure. Immunoblots revealed that chronic nicotine exposure significantly up-regulated mBDNF, p-Erk and p-Akt expression in the perilesion cortex of CCI mice. Immunofluorescence microscopy indicated that elevated mBDNF and p-Akt expression were mainly localized within cortical neurons. Immunolabelling of Iba1 demonstrated that chronic nicotine exposure attenuated microglia-mediated neuroinflammation. CONCLUSIONS AND IMPLICATIONS: Post-injury chronic nicotine exposure via vaping facilitates recovery of sensorimotor function by upregulating neuroprotective mBDNF/TrkB/Akt/Erk signalling. These findings suggest potential neuroprotective properties of nicotine despite its highly addictive nature. Thus, understanding the multifaceted effects of chronic nicotine exposure on TBI-associated symptoms is crucial for paving the way for informed and properly managed therapeutic interventions.

Novel drugs approved by the EMA, the FDA, and the MHRA in 2023: A year in review.

In 2023, seventy novel drugs received market authorization for the first time in either Europe (by the EMA and the MHRA) or in the United States (by the FDA). Confirming a steady recent trend, more than half of these drugs target rare diseases or intractable forms of cancer. Thirty drugs are categorized as "first-in-class" (FIC), illustrating the quality of research and innovation that drives new chemical entity discovery and development. We succinctly describe the mechanism of action of most of these FIC drugs and discuss the therapeutic areas covered, as well as the chemical category to which these drugs belong. The 2023 novel drug list also demonstrates an unabated emphasis on polypeptides (recombinant proteins and antibodies), Advanced Therapy Medicinal Products (gene and cell therapies) and RNA therapeutics, including the first-ever approval of a CRISPR-Cas9-based gene-editing cell therapy.

Modeling and Phenotyping Acute and Chronic Type 2 Diabetes Mellitus In Vitro in Rodent Heart and Skeletal Muscle Cells.

Type 2 diabetes (T2D) has a complex pathophysiology which makes modeling the disease difficult. We aimed to develop a novel model for simulating T2D in vitro, including hyperglycemia, hyperlipidemia, and variably elevated insulin levels targeting muscle cells. We investigated insulin resistance (IR), cellular respiration, mitochondrial morphometry, and the associated function in different T2D-mimicking conditions in rodent skeletal (C2C12) and cardiac (H9C2) myotubes. The physiological controls included 5 mM of glucose with 20 mM of mannitol as osmotic controls. To mimic hyperglycemia, cells were exposed to 25 mM of glucose. Further treatments included insulin, palmitate, or both. After short-term (24 h) or long-term (96 h) exposure, we performed radioactive glucose uptake and mitochondrial function assays. The mitochondrial size and relative frequencies were assessed with morphometric analyses using electron micrographs. C2C12 and H9C2 cells that were treated short- or long-term with insulin and/or palmitate and HG showed IR. C2C12 myotubes exposed to T2D-mimicking conditions showed significantly decreased ATP-linked respiration and spare respiratory capacity and less cytoplasmic area occupied by mitochondria, implying mitochondrial dysfunction. In contrast, the H9C2 myotubes showed elevated ATP-linked and maximal respiration and increased cytoplasmic area occupied by mitochondria, indicating a better adaptation to stress and compensatory lipid oxidation in a T2D environment. Both cell lines displayed elevated fractions of swollen/vacuolated mitochondria after T2D-mimicking treatments. Our stable and reproducible in vitro model of T2D rapidly induced IR, changes in the ATP-linked respiration, shifts in energetic phenotypes, and mitochondrial morphology, which are comparable to the muscles of patients suffering from T2D. Thus, our model should allow for the study of disease mechanisms and potential new targets and allow for the screening of candidate therapeutic compounds.

Understanding the Role of Caveolae in Oxygen Buffering: The Effect of Membrane Curvature.

The "oxygen paradox" can be explained as two opposing biological processes with oxygen (O2) as a reactant. On the one hand, oxygen is essential to aerobic metabolism, powering oxidative phosphorylation in mitochondria. On the other hand, an excess supply of oxygen will generate reactive species which are harmful for the cell. In healthy tissues, the first process must be maximized relative to the second one. We have hypothesized that curved and cholesterol-enriched membrane invaginations called caveolae help maintain the proper oxygen level by taking up oxygen and attenuating its release to the mitochondria. The mechanism by which caveolae may help to buffer the oxygen level in cells is still unclear. Here, we aim to assess how structural aspects of caveolae, the curvature of the membrane, influence the local oxygen abundance and the membrane partitioning. We have modelled a flat bilayer and a liposome composed of dipalmitoylphosphatidylcholine (DPPC), using molecular dynamics simulation. Associated changes in the membrane-level oxygen partition coefficient and free energy profiles will be presented.

Meditation-induced bloodborne factors as an adjuvant treatment to COVID-19 disease.

The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide. Management of the pandemic has relied mainly on SARS-CoV-2 vaccines, while alternative approaches such as meditation, shown to improve immunity, have been largely unexplored. Here, we probe the relationship between meditation and COVID-19 disease and directly test the impact of meditation on the induction of a blood environment that modulates viral infection. We found a significant inverse correlation between length of meditation practice and SARS-CoV-2 infection as well as accelerated resolution of symptomology of those infected. A meditation "dosing" effect was also observed. In cultured human lung cells, blood from experienced meditators induced factors that prevented entry of pseudotyped viruses for SARS-CoV-2 spike protein of both the wild-type Wuhan-1 virus and the Delta variant. We identified and validated SERPINA5, a serine protease inhibitor, as one possible protein factor in the blood of meditators that is necessary and sufficient for limiting pseudovirus entry into cells. In summary, we conclude that meditation can enhance resiliency to viral infection and may serve as a possible adjuvant therapy in the management of the COVID-19 pandemic.

Drug-Induced Thrombocytopenia: A Case Involving Vancomycin.

Drug-induced thrombocytopenia (DIT) is a rare adverse effect that occurs when administering various medications. The medications associated with this possible adverse effect include heparin, penicillin, furosemide, vancomycin, non-steroidal anti-inflammatory drugs, ranitidine, and many others. DIT causes a rapid decrease in platelet counts after drug administration and typically resolves once the offending agent has been discontinued. The induced thrombocytopenia increases the bleeding risk and possibility of adverse effects throughout a hospital course. In this case report, we look at the presenting symptoms and treatment course of an interesting case of DIT that occurred following the administration of vancomycin.

Mitochondrial impairment but not peripheral inflammation predicts greater Gulf War illness severity.

Gulf War illness (GWI) is an important exemplar of environmentally-triggered chronic multisymptom illness, and a potential model for accelerated aging. Inflammation is the main hypothesized mechanism for GWI, with mitochondrial impairment also proposed. No study has directly assessed mitochondrial respiratory chain function (MRCF) on muscle biopsy in veterans with GWI (VGWI). We recruited 42 participants, half VGWI, with biopsy material successfully secured in 36. Impaired MRCF indexed by complex I and II oxidative phosphorylation with glucose as a fuel source (CI&CIIOXPHOS) related significantly or borderline significantly in the predicted direction to 17 of 20 symptoms in the combined sample. Lower CI&CIIOXPHOS significantly predicted GWI severity in the combined sample and in VGWI separately, with or without adjustment for hsCRP. Higher-hsCRP (peripheral inflammation) related strongly to lower-MRCF (particularly fatty acid oxidation (FAO) indices) in VGWI, but not in controls. Despite this, whereas greater MRCF-impairment predicted greater GWI symptoms and severity, greater inflammation did not. Surprisingly, adjusted for MRCF, higher hsCRP significantly predicted lesser symptom severity in VGWI selectively. Findings comport with a hypothesis in which the increased inflammation observed in GWI is driven by FAO-defect-induced mitochondrial apoptosis. In conclusion, impaired mitochondrial function-but not peripheral inflammation-predicts greater GWI symptoms and severity.

Cancer-cell-secreted extracellular vesicles target p53 to impair mitochondrial function in muscle.

Skeletal muscle loss and weakness are associated with bad prognosis and poorer quality of life in cancer patients. Tumor-derived factors have been implicated in muscle dysregulation by inducing cachexia and apoptosis. Here, we show that extracellular vesicles secreted by breast cancer cells impair mitochondrial homeostasis and function in skeletal muscle, leading to decreased mitochondrial content and energy production and increased oxidative stress. Mechanistically, miR-122-5p in cancer-cell-secreted EVs is transferred to myocytes, where it targets the tumor suppressor TP53 to decrease the expression of TP53 target genes involved in mitochondrial regulation, including Tfam, Pgc-1α, Sco2, and 16S rRNA. Restoration of Tp53 in muscle abolishes mitochondrial myopathology in mice carrying breast tumors and partially rescues their impaired running capacity without significantly affecting muscle mass. We conclude that extracellular vesicles from breast cancer cells mediate skeletal muscle mitochondrial dysfunction in cancer and may contribute to muscle weakness in some cancer patients.

Loss of cAMP Signaling in CD11c Immune Cells Protects Against Diet-Induced Obesity.

In obesity, CD11c+ innate immune cells are recruited to adipose tissue and create an inflammatory state that causes both insulin and catecholamine resistance. We found that ablation of Gnas, the gene that encodes Gαs, in CD11c expressing cells protects mice from obesity, glucose intolerance, and insulin resistance. Transplantation studies showed that the lean phenotype was conferred by bone marrow-derived cells and did not require adaptive immunity. Loss of cAMP signaling was associated with increased adipose tissue norepinephrine and cAMP signaling, and prevention of catecholamine resistance. The adipose tissue had reduced expression of catecholamine transport and degradation enzymes, suggesting that the elevated norepinephrine resulted from decreased catabolism. Collectively, our results identified an important role for cAMP signaling in CD11c+ innate immune cells in whole-body metabolism by controlling norepinephrine levels in white adipose tissue, modulating catecholamine-induced lipolysis and increasing thermogenesis, which, together, created a lean phenotype. ARTICLE HIGHLIGHTS: We undertook this study to understand how immune cells communicate with adipocytes, specifically, whether cAMP signaling in the immune cell and the adipocyte are connected. We identified a reciprocal interaction between CD11c+ innate immune cells and adipocytes in which high cAMP signaling in the immune cell compartment induces low cAMP signaling in adipocytes and vice versa. This interaction regulates lipolysis in adipocytes and inflammation in immune cells, resulting in either a lean, obesity-resistant, and insulin-sensitive phenotype, or an obese, insulin-resistant phenotype.

Impact of blood factors on endothelial cell metabolism and function in two diverse heart failure models.

Role of blood-based factors in development and progression of heart failure (HF) is poorly characterized. Blood contains factors released during pathophysiological states that may impact cellular function and provide mechanistic insights to HF management. We tested effects of blood from two distinct HF models on cardiac metabolism and identified possible cellular targets of the effects. Blood plasma was obtained from daunorubicin- and myocardial infarction-induced HF rabbits (Dauno-HF and MI-HF) and their controls (Dauno-Control and MI-Control). Effects of plasma on bioenergetics of myocardial tissue from healthy mice and cellular cardiac components were assessed using high-resolution respirometry and Seahorse flux analyzer. Since endothelial cell respiration was profoundly affected by HF plasma, effects of plasma on endothelial cell barrier function and death were further evaluated. Western-blotting and electron microscopy were performed to evaluate mitochondrial proteins and morphology. Brief exposure to HF plasma decreased cardiac tissue respiration. Endothelial cell respiration was most impacted by exposure to HF plasma. Endothelial cell monolayer integrity was decreased by incubation with Dauno-HF plasma. Apoptosis and necrosis were increased in cells incubated with Dauno-HF plasma for 24 h. Down-regulation of voltage-dependent anion-selective channel (VDAC)-1, translocase of outer membrane 20 (Tom20), and mitochondrial fission factor (MFF) in cells exposed to Dauno-HF plasma and mitochondrial signal transducer and activator of transcription 3 (Stat3) and MFF in cells exposed to MI-HF plasma were observed. Mitochondrial structure was disrupted in cells exposed to HF plasma. These findings indicate that endothelial cells and mitochondrial structure and function may be primary target where HF pathology manifests and accelerates. High-throughput blood-based screening of HF may provide innovative ways to advance disease diagnosis and management.

Guidance for the use and reporting of anaesthetic agents in BJP manuscripts involving work with animals.

Scientists who plan to publish in the British Journal of Pharmacology (BJP) should read this article before undertaking studies utilising anaesthetics in mammalian animals. This editorial identifies certain gaps in the reporting of details on the use of anaesthetics in animal research studies published in the BJP. The editorial also provides guidance, based upon current best practices, for performing in vivo experiments that require anaesthesia. In addition, mechanisms of action and physiological impact of specific anaesthetic agents are discussed. Our goal is to identify best practices and to provide guidance on the information required for manuscripts submitted to the BJP that involve the use of anaesthetic agents in studies with experimental animals.

Very Low Driving-Pressure Ventilation in Patients With COVID-19 Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation: A Physiologic Study.

OBJECTIVES: To determine in patients with acute respiratory distress syndrome (ARDS) on venovenous extracorporeal membrane oxygenation (VV ECMO) whether reducing driving pressure (ΔP) would decrease plasma biomarkers of inflammation and lung injury (interleukin-6 [IL-6], IL-8, and the soluble receptor for advanced glycation end-products sRAGE). DESIGN: A single-center prospective physiologic study. SETTING: At a single university medical center. PARTICIPANTS: Adult patients with severe COVID-19 ARDS on VV ECMO. INTERVENTIONS: Participants on VV ECMO had the following biomarkers measured: (1) pre-ECMO with low-tidal-volume ventilation (LTVV), (2) post-ECMO with LTVV, (3) during low-driving-pressure ventilation (LDPV), (4) after 2 hours of very low driving-pressure ventilation (V-LDPV, main intervention ΔP = 1 cmH2O), and (5) 2 hours after returning to LDPV. MAIN MEASUREMENTS AND RESULTS: Twenty-six participants were enrolled; 21 underwent V-LDPV. There was no significant change in IL-6, IL-8, and sRAGE from LDPV to V-LDPV and from V-LDPV to LDPV. Only participants (9 of 21) with nonspontaneous breaths had significant change (p < 0.001) in their tidal volumes (Vt) (mean ± SD), 1.9 ± 0.5, 0.1 ± 0.2, and 2.0 ± 0.7 mL/kg predicted body weight (PBW). Participants with spontaneous breathing, Vt were unchanged-4.5 ± 3.1, 4.7 ± 3.1, and 5.6 ± 2.9 mL/kg PBW (p = 0.481 and p = 0.065, respectively). There was no relationship found when accounting for Vt changes and biomarkers. CONCLUSIONS: Biomarkers did not significantly change with decreased ΔPs or Vt changes during the first 24 hours post-ECMO. Despite deep sedation, reductions in Vt during V-LDPV were not reliably achieved due to spontaneous breaths. Thus, patients on VV ECMO for ARDS may have higher Vt (ie, transpulmonary pressure) than desired despite low ΔPs or Vt.

EVESTA: Emergency VESTibular Algorithm and its impact on the acute management of benign paroxysmal positional vertigo.

OBJECTIVE: To synthesise evidence-based research concerning the assessment and management of acute dizziness via construction of a comprehensive clinical algorithm. Assess its clinical impact with an aim to improve the acute management of benign paroxysmal positional vertigo (BPPV) within Wyong Public Hospital ED in four key recommendations. METHOD: Current best practice models of care were synthesised into a single clinical, district-based peer-reviewed algorithm by a specialist focus group. An observational pre- and post-implementation study was completed to assess the impact of the algorithm on the management of BPPV. A total of 162 notes (pre [control] n = 87 and post [intervention] n = 75) met the inclusion criteria. Adherence to the BPPV clinical practice guidelines statements 1a, 3a, 4a and 6 were analysed for statistical difference in practice between the two groups. RESULTS: Following implementation of the Emergency VESTibular Algorithm (EVESTA), compliance showed a significant improvement in Hallpike-Dix performed by 27% (95% confidence interval [CI] 14-40%; defects pre-intervention 40%: post-intervention 13%) (P < 0.001), utilisation of neuroimaging reduced by 16% (95% CI 2-30%; 40%: 24%) (P < 0.05), repositioning techniques performed increased by 33% (95% CI 18-48%; 68%: 36%) (P < 0.001). Administration of vestibular suppressant medication reduced by 30% (95% CI 15-45%; 59%: 29%) (P < 0.001). An interrupted time series analysis confirmed significant change in BPPV admissions post-project -4.23% (95% CI -7.20, -1.27%) (P = 0.041). CONCLUSION: Diagnosis and management of acute dizziness is challenging within the ED. Synthesis of best practice into a clinical algorithm has improved the diagnosis and evidence-based treatment of BPPV. There is continued opportunity to improve the efficiency and effectiveness in the management of both central and peripheral acute dizziness within the ED.

Subpial delivery of adeno-associated virus 9-synapsin-caveolin-1 (AAV9-SynCav1) preserves motor neuron and neuromuscular junction morphology, motor function, delays disease onset, and extends survival in hSOD1G93A mice.

Elevating neuroprotective proteins using adeno-associated virus (AAV)-mediated gene delivery shows great promise in combating devastating neurodegenerative diseases. Amyotrophic lateral sclerosis (ALS) is one such disease resulting from loss of upper and lower motor neurons (MNs) with 90-95% of cases sporadic (SALS) in nature. Due to the unknown etiology of SALS, interventions that afford neuronal protection and preservation are urgently needed. Caveolin-1 (Cav-1), a membrane/lipid rafts (MLRs) scaffolding and neuroprotective protein, and MLR-associated signaling components are decreased in degenerating neurons in postmortem human brains. We previously showed that, when crossing our SynCav1 transgenic mouse (TG) with the mutant human superoxide dismutase 1 (hSOD1G93A) mouse model of ALS, the double transgenic mouse (SynCav1 TG/hSOD1G93A) exhibited better motor function and longer survival. The objective of the current study was to test whether neuron-targeted Cav-1 upregulation in the spinal cord using AAV9-SynCav1 could improve motor function and extend longevity in mutant humanized mouse and rat (hSOD1G93A) models of familial (F)ALS. Methods: Motor function was assessed by voluntary running wheel (RW) in mice and forelimb grip strength (GS) and motor evoked potentials (MEP) in rats. Immunofluorescence (IF) microscopy for choline acetyltransferase (ChAT) was used to assess MN morphology. Neuromuscular junctions (NMJs) were measured by bungarotoxin-a (Btx-a) and synaptophysin IF. Body weight (BW) was measured weekly, and the survival curve was determined by Kaplan-Meier analysis. Results: Following subpial gene delivery to the lumbar spinal cord, male and female hSOD1G93A mice treated with SynCav1 exhibited delayed disease onset, greater running-wheel performance, preserved spinal alpha-motor neuron morphology and NMJ integrity, and 10% increased longevity, independent of affecting expression of the mutant hSOD1G93A protein. Cervical subpial SynCav1 delivery to hSOD1G93A rats preserved forelimb GS and MEPs in the brachial and gastrocnemius muscles. Conclusion: In summary, subpial delivery of SynCav1 protects and preserves spinal motor neurons, and extends longevity in a familial mouse model of ALS without reducing the toxic monogenic component. Furthermore, subpial SynCav1 delivery preserved neuromuscular function in a rat model of FALS. The latter findings strongly indicate the therapeutic applicability of SynCav1 to treat ALS attributed to monogenic (FALS) and potentially in sporadic cases (i.e., SALS).

Age-Dependent Behavioral and Metabolic Assessment of App NL-G-F/NL-G-F Knock-in (KI) Mice.

Mitochondria play a crucial role in Alzheimer's disease (AD) onset and progression. Traditional transgenic AD mouse models which were widely used in the past decades share a common limitation: The overexpression of APP and overproduction of amyloid-beta (Aß) are accompanied by other APP peptide fragments, which could introduce artificial and non-clinically relevant phenotypes. Here, we performed an in-depth and time-resolved behavioral and metabolic characterization of a clinically relevant AD mouse model engineered to express normal physiological levels of APP harboring humanized Swedish (K670N/M671L), Beyreuther/Iberian (I716F), and Arctic (E693G) mutations (App NL-G-F/NL-G-F ), termed APP knock-in (APPKI) mice. Our result showed that APPKI mice exhibited fear learning deficits at 6-m age and contextual memory deficit at 12-m age. Histopathological analysis revealed mild amyloidosis (6E10) accompanied by microgliosis (Iba1) as early as 3 months, which progressed significantly together with significant astrocytosis at 6 and 12 m. We further analyzed hippocampal mitochondrial dysfunction by multiple assays, while 3-m APPKI mice brain mitochondrial function remains a similar level as WT mice. Significant mitochondrial dysfunction characterized by decreased ATP production and higher membrane potential with subsequent overproduction of reactive oxygen species (ROS) was observed in mitochondria isolated from 7-m APPKI mice hippocampal tissue. Morphologically, these mitochondria were larger in volume with a decreased level of mitochondrial fusion protein mitofusin-2 (MFN2). At 12 months, APPKI mice exhibit a significantly decreased total mitochondrial oxygen consumption rate (OCR) in isolated hippocampal mitochondria detected by high-resolution respirometry. These data indicate early mitochondrial dysfunction in the brain at pre-symptomatic age in the App NL-G-F/NL-G-mice, which may play a key role in the progression of the disease. Moreover, the identified behavioral and bioenergetic alterations in this clinically relevant AD mouse model provide a valuable tool to optimize the temporal component for therapeutic interventions to treat AD.

Planning experiments: Updated guidance on experimental design and analysis and their reporting III.

Scientists who plan to publish in British Journal of Pharmacology (BJP) must read this article before undertaking a study. This editorial provides guidance for the design of experiments. We have published previously two guidance documents on experimental design and analysis (Curtis et al., 2015; Curtis et al., 2018). This update clarifies and simplifies the requirements on design and analysis for BJP manuscripts. This editorial also details updated requirements following an audit and discussion on best practice by the BJP editorial board. Explanations for the requirements are provided in the previous articles. Here, we address new issues that have arisen in the course of handling manuscripts and emphasise three aspects of design that continue to present the greatest challenge to authors: randomisation, blinded analysis and balance of group sizes.