A simple procedure for estimation of total body surface area and determination of a new value of Meeh's constant in rats

Can the use of vitamin D-fortified sunscreen cream be the solution to the vitamin D deficiency pandemic?

Current approaches to vitamin D supplementation are generally limited to its oral intake. In this experimental study, the effects of applying vitamin D-fortified sunscreen creams to the skin on the absorption, and therefore levels of serum vitamin D metabolites were investigated. Forty 8-week-old male Wistar Albino rats were used in the study. Eight rats (Group B) were sacrificed to determine the baseline values of biochemical parameters. The remaining 32 rats were randomly divided into 4 equal groups as follows: Group S, only the back skin of the rats were shaved; Group SD, only vitamin D3 diluted with sunflower oil was applied to the shaved area; Group SC, only sunscreen cream was applied to the shaved area; and Group SDC, sunscreen cream fortified with vitamin D3 was applied to the shaved area. Serum 25(OH)D3 and 24,25(OH)2D3 levels were determined at the end of 8 weeks. Mean (± SD) serum 25(OH)D3 levels of groups B, S, SD, SC, and SDC were determined as 17.7 ± 5.7, 13.5 ± 3.1, 54.1 ± 13.0, 19.6 ± 2.7, 67.2 ± 16.5 ng/mL, respectively. There were statistically significant differences in serum 25(OH)D3 values between groups S and SD (p < 0.001) and between groups SC and SDC (p = 0.002). A positive correlation was found between serum 25(OH)D3 and 24,25(OH)2D3 parameters (r = 0.772; p < 0.001). With this study, it was concluded that vitamin D-fortified sunscreen cream increases serum vitamin D levels by exerting transdermal activity. Further studies are required to confirm this observations.

Impact of Right Ventricular Pressure Overload on Myocardial Stiffness Assessed by Natural Wave Imaging

BACKGROUND

Right ventricular (RV) hemodynamic performance determines the prognosis of patients with RV pressure overload. Using ultrafast ultrasound, natural wave velocity (NWV) induced by cardiac valve closure was proposed as a new surrogate to quantify myocardial stiffness.

OBJECTIVES

This study aimed to assess RV NWV in rodent models and children with RV pressure overload vs control subjects and to correlate NWV with RV hemodynamic parameters.

METHODS

Six-week-old rats were randomized to pulmonary artery banding (n = 6), Sugen hypoxia-induced pulmonary arterial hypertension (n = 7), or sham (n = 6) groups. They underwent natural wave imaging, echocardiography, and hemodynamic assessment at baseline and 6 weeks postoperatively. The authors analyzed NWV after tricuspid and after pulmonary valve closure (TVC and PVC, respectively). Conductance catheters were used to generate pressure-volume loops. In parallel, the authors prospectively recruited 14 children (7 RV pressure overload; 7 age-matched control subjects) and compared RV NWV with echocardiographic and invasive hemodynamic parameters.

RESULTS

NWV significantly increased in RV pressure overload rat models (4.99 ± 0.27 m/s after TVC and 5.03 ± 0.32 m/s after PVC in pulmonary artery banding at 6 weeks; 4.89 ± 0.26 m/s after TVC and 4.84 ± 0.30 m/s after PVC in Sugen hypoxia at 6 weeks) compared with control subjects (2.83 ± 0.15 m/s after TVC and 2.72 ± 0.34 m/s after PVC). NWV after TVC correlated with both systolic and diastolic parameters including RV dP/dtmax (r = 0.75; P < 0.005) and RV Ees (r = 0.81; P < 0.005). NWV after PVC correlated with both diastolic and systolic parameters and notably with RV end-diastolic pressure (r = 0.65; P < 0.01). In children, NWV after both right valves closure in RV pressure overload were higher than in healthy volunteers (P < 0.01). NWV after PVC correlated with RV E/E' (r = 0.81; P = 0.008) and with RV chamber stiffness (r = 0.97; P = 0.03).

CONCLUSIONS

Both RV early-systolic and early-diastolic myocardial stiffness show significant increase in response to pressure overload. Based on physiology and our observations, early-systolic myocardial stiffness may reflect contractility, whereas early-diastolic myocardial stiffness might be indicative of diastolic function.

Use of computed tomography to determine body surface area and K-constant in Atlantic Stingrays for chemotherapeutic dosing

OBJECTIVE

The objective of this study was to use body surface area (BSA) obtained via computed tomography (CT) to calculate a species-specific shape constant (K) and provide a formula for BSA based on body weight (BW) in Atlantic Stingrays Hypanus sabina. Ultimately, this information can be used to more accurately calculate chemotherapeutic doses and other metabolic-related measures.

METHODS

Six deceased Atlantic Stingrays of unknown age and with a range of sizes were collected during a natural mortality event and underwent CT scans. Following the scans, three-dimensional surface models were created from the imaging data to measure BSAs and derive a BSA formula based on BW. Nonlinear regression analysis of BSA versus thawed BW was performed, and a species-specific formula was derived.

RESULT

Body surface area (mean ± standard deviation) was 2015.01 ± 1115.02 cm2 (median = 1841.40 cm2; range = 844.2-4043.12 cm2). The calculated K-constant was 14.9 for the six Atlantic Stingrays, and the CT-derived BSA formula was as follows: BSA (cm2) = 14.9 × (BW, g)2/3.

CONCLUSION

These results provide a method for calculating BSA in Atlantic Stingrays. The CT-derived BSA formula can be used for allometric dosing of chemotherapeutic agents and other drugs in a clinical setting; in a broader sense, the formula can be applied to studies of nutrition, metabolic rate, and physiology.

The sports performance improving effects of konjac glucomannan with varying molecular weights in overtrained mice

Overtraining affects individuals engaged in high-volume training, potentially hindering athletic performance and revealing shortcomings in suggested solutions. This study evaluated the impact of konjac glucomannan (KGM) with varying molecular weights on the gut microbiome, endurance, and strength in mice subjected to excessive training. The native KGM (1.82 × 107 Da) was enzymatically degraded using endo-1,4-β-mannanase to generate moderate molecular weight KGM (KGM-EM, 1.89 × 105 Da) and low molecular weight KGM (KGM-EL, 1.34 × 104 Da). These fractions were characterized and compared with the native KGM regarding their effects on mice undergoing excessive training. The results demonstrated a positive correlation between KGM's molecular weight and its capacity to mitigate the adverse impacts of excessive training on strength or/and endurance (a significant increase of 55.57 % and 55.70 % by the native KGM compared with the excessive training group). In addition, the native KGM exhibited superior preservation of microbial diversity and composition in fecal samples against excessive training-induced shifts, along with increased production of individual and total short-chain fatty acids in plasma compared with the two degraded products. Overall, these results highlight the potential benefits of high molecular weight KGM for preventing overtraining syndrome and enhancing athletic performance in animal models.

The impact of subdermal adipose derived stem cell injections and early excision on systemic oxidative stress and wound healing in rats with severe scald burns

AIM

This study aims to develop an experimental treatment model effective against oxidative stress in the acute period of severe burns and to analyze the mechanisms of healing large wound defects.

METHODS

Five rats, including 2 females and 3 males, were used as donors to obtain adipose-derived stem cells (ADSC) from the inguinal fat pad. The stem cells were labeled with green fluorescent protein. The study included four groups of 17 rats, each with grade 3 scalding burns on 30 % of their body surface, and a control group of 10 rats with an equal number of males and females. After early excision, 106 ADSC-derived stem cells were administered subdermally to the burned wound and autografted to the stem cell group (n = 17). The early excision group (n = 17) received early excision and autograft, with 2 ml of normal saline injected subdermally into the burn wound edge. The PLM group (n = 17) was treated with a polylactic membrane (PLM) dressing after the burn. No treatment was given to the burn group (n = 17). Ten rats from all groups were sacrificed on the 4th day post-burn for oxidative stress evaluation. The control group (n = 10) was sacrificed on day 4. Blood and tissue samples were collected post-sacrifice. Oxidative stress and inflammation in the blood, as well as cell damage in the skin, liver, kidneys, and lungs, were investigated histopathologically and biochemically on the 4th day post-burn. On the 70th day after burn, wound healing was examined macroscopically and histopathologically.

RESULTS

On the 4th day, oxidative stress results showed that the levels of Total Oxidative Capacity (TOC) in the blood were lowest in the stem cell (7.4 [6-8.8]), control (6.7 [5.9-7.6]), and early excision (7.5 [6.6-8.5]) groups, with no significant difference between them. The burn group (14.7 [12.5-16.9]) had the highest TOC levels. The PLM group (9.7 [8.6-10.7]) had lower TOC levels than the burn group but higher levels than the other groups. Histopathological examination on the 4th day revealed low liver caspase-3 immunoreactivity in the stem cell and early excision groups among the burn groups. Caspase-3 immunoreactivity levels were as follows: stem cell group (20 [10-30]), early excision group (25 [15-50]), PLM group (70 [50-100]), control group (0), and burn group (80 [60-120]). Other oxidative stress and end-organ damage outcomes were consistent with these results. All rats in the stem cell group had burn wounds that healed completely by the 70th day. Examination of the skin and its appendages from the stem cell group with an immunofluorescence microscope demonstrated green coloration, indicating incorporation of stem cells.

CONCLUSION

Stem cells may have the potential to form new skin and its appendages, providing better healing for large skin defects. Early excision treatment, by removing local necrotic tissues after extensive and deep burns, can prevent end-organ damage due to systemic oxidative stress and inflammation. We also believe that when these two treatments are used together, they can achieve the best results.

The Wound-Healing Effect of a Novel Fibroblasts-Impregnated Hydroxyethylcellulose Gel in a Rat Full-Thickness Burn Model: A Preclinical Study

Background/Objectives: The objective of this study was to assess the efficacy of a cell-containing wound dressing based on fibroblasts in hydroxyethylcellulose (HEC) gel for the local treatment of deep partial-thickness and/or full-thickness skin burns in an animal model. Methods: The rats (male Wistar, n = 100) were subjected to a full-thickness thermal burn (16 cm2). Radical necrectomy was performed one day after the burn. Three days later, the rats were randomly assigned to one of four groups: group 1 (no treatment), group 2 (chloramphenicol and methyluracil ointment, a routine clinical treatment), group 3 (a gel without cells, mock treatment), and group 4 (a dermal fibroblast-impregnated HEC gel). The treatment lasted for five days. The wound-healing process was evaluated by planimetric, cytologic, histologic, and immunohistochemical methods. Results: The differences in the rate of wound healing and the characteristics of wound cytology were identified. In the group 4, a regenerative type of cytogram was revealed, characterized by a significantly increased number of fibroblastic cells in comparison to samples from non-treated and mock-treated animals. Biopsy samples of burn wounds from animals in the group 4l demonstrated the presence of mature granulation tissue and a large number of microvessels. The repair process was stimulated, as evidenced by the increased thickness of newly formed granulation tissue and epidermis in the wound zone, elevated cellularity, and enhanced re-epithelialization activity. The number of Ki-67-positive proliferating cells was significantly higher in group 4 than in the control groups). A small number of non-proliferating donor fibroblasts was observed in the wound area 3 days after the end of treatment. Conclusions: The cell product is an effective agent for promoting wound healing during the regenerative phase. The experiments demonstrated that a gel populated by dermal fibroblasts can stimulate reparative regeneration processes in deep partial- and full-thickness burn wounds.

The Abl1 tyrosine kinase is a key player in doxorubicin-induced cardiomyopathy and its p53/p73 cell death mediated signaling differs in atrial and ventricular cardiomyocytes

BACKGROUND

Doxorubicin is an important anticancer drug, however, elicits dose-dependently cardiomyopathy. Given its mode of action, i.e. topoisomerase inhibition and DNA damage, we investigated genetic events associated with cardiomyopathy and searched for mechanism-based possibilities to alleviate cardiotoxicity. We treated rats at clinically relevant doses of doxorubicin. Histopathology and transmission electron microscopy (TEM) defined cardiac lesions, and transcriptomics unveiled cardiomyopathy-associated gene regulations. Genomic-footprints revealed critical components of Abl1-p53-signaling, and EMSA-assays evidenced Abl1 DNA-binding activity. Gene reporter assays confirmed Abl1 activity on p53-targets while immunohistochemistry/immunofluorescence microscopy demonstrated Abl1, p53&p73 signaling.

RESULTS

Doxorubicin treatment caused dose-dependently toxic cardiomyopathy, and TEM evidenced damaged mitochondria and myofibrillar disarray. Surviving cardiomyocytes repressed Parkin-1 and Bnip3-mediated mitophagy, stimulated dynamin-1-like dependent mitochondrial fission and induced anti-apoptotic Bag1 signaling. Thus, we observed induced mitochondrial biogenesis. Transcriptomics discovered heterogeneity in cellular responses with minimal overlap between treatments, and the data are highly suggestive for distinct cardiomyocyte (sub)populations which differed in their resilience and reparative capacity. Genome-wide footprints revealed Abl1 and p53 enriched binding sites in doxorubicin-regulated genes, and we confirmed Abl1 DNA-binding activity in EMSA-assays. Extraordinarily, Abl1 signaling differed in the heart with highly significant regulations of Abl1, p53 and p73 in atrial cardiomyocytes. Conversely, in ventricular cardiomyocytes, Abl1 solely-modulated p53-signaling that was BAX transcription-independent. Gene reporter assays established Abl1 cofactor activity for the p53-reporter PG13-luc, and ectopic Abl1 expression stimulated p53-mediated apoptosis.

CONCLUSIONS

The tyrosine kinase Abl1 is of critical importance in doxorubicin induced cardiomyopathy, and we propose its inhibition as means to diminish risk of cardiotoxicity.

Effect of placental mesenchymal stem cells on promoting the healing of chronic burn wounds

The treatment of chronic burn wounds is difficult in clinical practice. The ideal therapy is required to be continuously explored. Mesenchymal stem cells revolutionize the treatment of many diseases. The placental mesenchymal stem cells (PMSCs) have the characteristics of easy access, strong proliferation ability and multi-directional differentiation potential. The aim of this study was to investigate the potential of PMSCs in chronic burn wound healing. In this study, species of bacteria of 317 patients with chronic burn wounds have been analyzed. Samples of chronic burn wound fluid were collected from representative patients and then co-cultured with cells. In vitro studies showed that chronic burn wound fluid inhibited the proliferation of human keratinocytes and fibroblasts, while PMSCs can counteract the effects of burn wound fluid on inhibiting the proliferation and migration of human keratinocytes and fibroblasts. In addition, in vivo studies showed that a rat chronic burn wound model was successfully created. The expression of MMP-2, MMP-9, MDA, IL-6 and TNF-α in chronic burn wounds was significantly higher than that in acute burn wounds. Finally, the rat chronic burn wound model was used to verify that placental mesenchymal stem cell transplantation increased the wound healing rate, decreased the wound healing time, and promoted wound healing by increasing the thickness of epidermis and promoting the expression of P63 and CK10. The findings provide support for the hypothesis that PMSCs promote the repair of chronic burn wounds and key scientific data for the application of PMSCs as a new method for treating chronic burn wounds.

Integrative gene regulatory network analysis discloses key driver genes of fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a poorly understood disease affecting 3-5% of adult females. The pathobiology of FMD involves arterial lesions of stenosis, dissection, tortuosity, dilation and aneurysm, which can lead to hypertension, stroke, myocardial infarction and even death. Currently, there are no animal models for FMD and few insights as to its pathobiology. In this study, by integrating DNA genotype and RNA sequence data from primary fibroblasts of 83 patients with FMD and 71 matched healthy controls, we inferred 18 gene regulatory co-expression networks, four of which were found to act together as an FMD-associated supernetwork in the arterial wall. After in vivo perturbation of this co-expression supernetwork by selective knockout of a top network key driver, mice developed arterial dilation, a hallmark of FMD. Molecular studies indicated that this supernetwork governs multiple aspects of vascular cell physiology and functionality, including collagen/matrix production. These studies illuminate the complex causal mechanisms of FMD and suggest a potential therapeutic avenue for this challenging disease.

Effect of Chronic Dolutegravir Administration on the Trace Amine Profile in Wistar Rats

BACKGROUND

Dolutegravir (DTG), an integrase strand inhibitor, is currently used as the first-line treatment for HIV. Despite relatively poor tissue penetration, the risk of adverse effects in metabolic and excretory systems should be considered. The trace aminergic system and trace amines are emerging as relevant role players in many chronic diseases that are commonly diagnosed but poorly understood. Trace amines are biogenic amines that are endogenously produced and can also be ingested by the intake of trace amine-rich food. Trace amines are known to differentially regulate inflammatory and neurological outcome.

OBJECTIVE

This study investigated the effects of DTG on the trace amine profile in a wistar rat model.

METHODS

A total of 24 healthy wistar rats were randomly divided into four experimental groups: male and female controls and male and female DTG-treated. Blood and tissue samples were collected following a 12-week DTG administration study. Liquid chromatography-tandem mass spectroscopy (LC-MS/MS) was used to determine trace amine concentrations in urine, plasma, brain, and gastrointestinal tissue.

RESULTS

Current data illustrate that polyamines differ significantly (p < 0.05) between males and females in various matrices. DTG significantly (p < 0.05) reduced jejunal tyramine and urinary synephrine levels.

CONCLUSION

Data do not raise major concerns about DTG in the context of the trace amine profile. However, given the importance of the dysregulated trace amine profile in various diseased states, including HIV, current data warrant clinical investigation to further evaluate the significance of DTG-associated effects on the trace amine profile.

Fecal SN-38 Content as a Surrogate Predictor of Intestinal SN-38 Exposure and Associated Irinotecan-induced Severe Delayed-Onset Diarrhea by a Novel Use of the Spectrofluorimetric Method

BACKGROUND

Irinotecan administration can lead to severe delayed-onset diarrhea (SDOD) in clinical practice. Currently, there is no reliable surrogate predictor of intestinal exposure to SN-38 and subsequent diarrhea incidence.

METHODS

The relationship between fecal 7-ethyl-10-hydroxycamptothecin (SN-38) content and SDOD was investigated in Fisher 344 rats using a novel spectrofluorimetric method. Additionally, a pharmacokinetic study of irinotecan was performed to evaluate the biodistribution of SN-38 to establish the relationship between tissue and fecal SN-38 exposure.

RESULTS

The spectrofluorimetric method was successfully employed to measure fecal SN-38 and CPT-11 content from Day 3 to Day 6 post-irinotecan administration. Only fecal SN-38 content on Day 3 exhibited a significantly positive correlation with SDOD incidence on Days 4 and 5. A cutoff value of SN-38 ≥ 0.066 mg/g in feces was identified, predicting severe diarrhea incidence with 81% accuracy and 80% specificity. The positive correlation between fecal SN-38 content and SN-38 exposure in the ileum on Day 3 was also reflected in the changes of indicators during intestinal injury, such as prostaglandin E2 level and antioxidant activity.

CONCLUSION

Fecal SN-38 content proves to be representative of intestinal exposure to SN-38, indicative of intestinal injury, and predictive of SDOD incidence in rats, while the spectrofluorimetric method demonstrates the translational potential.

Systemic inflammation following traumatic injury and its impact on neuroinflammatory gene expression in the rodent brain

BACKGROUND

Trauma can result in systemic inflammation that leads to organ dysfunction, but the impact on the brain, particularly following extracranial insults, has been largely overlooked.

METHODS

Building upon our prior findings, we aimed to understand the impact of systemic inflammation on neuroinflammatory gene transcripts in eight brain regions in rats exposed to (1) blast overpressure exposure [BOP], (2) cutaneous thermal injury [BU], (3) complex extremity injury, 3 hours (h) of tourniquet-induced ischemia, and hind limb amputation [CEI+tI+HLA], (4) BOP+BU or (5) BOP+CEI and delayed HLA [BOP+CEI+dHLA] at 6, 24, and 168 h post-injury (hpi).

RESULTS

Globally, the number and magnitude of differentially expressed genes (DEGs) correlated with injury severity, systemic inflammation markers, and end-organ damage, driven by several chemokines/cytokines (Csf3, Cxcr2, Il16, and Tgfb2), neurosteroids/prostaglandins (Cyp19a1, Ptger2, and Ptger3), and markers of neurodegeneration (Gfap, Grin2b, and Homer1). Regional neuroinflammatory activity was least impacted following BOP. Non-blast trauma (in the BU and CEI+tI+HLA groups) contributed to an earlier, robust and diverse neuroinflammatory response across brain regions (up to 2-50-fold greater than that in the BOP group), while combined trauma (in the BOP+CEI+dHLA group) significantly advanced neuroinflammation in all regions except for the cerebellum. In contrast, BOP+BU resulted in differential activity of several critical neuroinflammatory-neurodegenerative markers compared to BU. t-SNE plots of DEGs demonstrated that the onset, extent, and duration of the inflammatory response are brain region dependent. Regardless of injury type, the thalamus and hypothalamus, which are critical for maintaining homeostasis, had the most DEGs. Our results indicate that neuroinflammation in all groups progressively increased or remained at peak levels over the study duration, while markers of end-organ dysfunction decreased or otherwise resolved.

CONCLUSIONS

Collectively, these findings emphasize the brain's sensitivity to mediators of systemic inflammation and provide an example of immune-brain crosstalk. Follow-on molecular and behavioral investigations are warranted to understand the short- to long-term pathophysiological consequences on the brain, particularly the mechanism of blood-brain barrier breakdown, immune cell penetration-activation, and microglial activation.

Right ventricular diastolic adaptation to pressure overload in different rat strains

Different rat strains are used in various animal models of pulmonary hypertension and right ventricular (RV) failure. No systematic assessment has been made to test differences in RV response to pressure overload between rat strains. We compared RV adaptation to pulmonary trunk banding (PTB) in Wistar (W), Sprague Dawley (SD), and Fischer344 (F) rats by hemodynamic profiling focusing on diastolic function. Age-matched male rat weanlings were randomized to sham surgery (W-sham, n = 5; SD-sham, n = 4; F-sham, n = 4) or PTB (W-PTB, n = 8; SD-PTB, n = 8; F-PTB, n = 8). RV function was evaluated after 5 weeks by echocardiography, cardiac MRI, and invasive pressure-volume measurements. PTB caused RV failure and increased RV systolic pressures four-fold in all three PTB groups compared with sham. W- and SD-PTB had a 2.4-fold increase in RV end-systolic volume index compared with sham, while F-PTB rats were less affected. Diastolic and right atrial impairment were evident by increased RV end-diastolic elastance, filling pressure, and E/e' in PTB rats compared with sham, again F-PTB the least affected. In conclusions, PTB caused RV failure with signs of diastolic dysfunction. Despite a similar increase in RV systolic pressure, F-PTB rats showed less RV dilatation and a more preserved diastolic function compared with W- and SD-PTB.

Pre-Incisional and Multiple Intradermal Injection of N-Acetylcysteine Slightly Improves Incisional Wound Healing in an Animal Model

The objective of this study was to investigate if delivering multiple doses of N-acetylcysteine (NAC) post-surgery in addition to pre-incisional administration significantly impacts the wound healing process in a rat model. Full-thickness skin incisions were carried out on the dorsum of 24 Sprague-Dawley rats in six locations. Fifteen minutes prior to the incision, half of the sites were treated with a control solution, with the wounds on the contralateral side treated with solutions containing 0.015%, 0.03% and 0.045% of NAC. In the case of the NAC treated group, further injections were given every 8 h for three days. On days 3, 7, 14 and 60 post-op, rats were sacrificed to gather material for the histological analysis, which included histomorphometry, collagen fiber organization analysis, immunohistochemistry and Abramov scale scoring. It was determined that scars treated with 0.015% NAC had significantly lower reepithelization than the control at day 60 post-op (p = 0.0018). Scars treated with 0.045% NAC had a significantly lower collagen fiber variance compared to 0.015% NAC at day 14 post-op (p = 0.02 and p = 0.04) and a lower mean scar width than the control at day 60 post-op (p = 0.0354 and p = 0.0224). No significant differences in the recruitment of immune cells and histological parameters were found. The results point to a limited efficacy of multiple NAC injections post-surgery in wound healing.

Age-related ciliopathy: Obesogenic shortening of melanocortin-4 receptor-bearing neuronal primary cilia

Obesity is often associated with aging. However, the mechanism of age-related obesity is unknown. The melanocortin-4 receptor (MC4R) mediates leptin-melanocortin anti-obesity signaling in the hypothalamus. Here, we discovered that MC4R-bearing primary cilia of hypothalamic neurons progressively shorten with age in rats, correlating with age-dependent metabolic decline and increased adiposity. This "age-related ciliopathy" is promoted by overnutrition-induced upregulation of leptin-melanocortin signaling and inhibited or reversed by dietary restriction or the knockdown of ciliogenesis-associated kinase 1 (CILK1). Forced shortening of MC4R-bearing cilia in hypothalamic neurons by genetic approaches impaired neuronal sensitivity to melanocortin and resulted in decreased brown fat thermogenesis and energy expenditure and increased appetite, finally developing obesity and leptin resistance. Therefore, despite its acute anti-obesity effect, chronic leptin-melanocortin signaling increases susceptibility to obesity by promoting the age-related shortening of MC4R-bearing cilia. This study provides a crucial mechanism for age-related obesity, which increases the risk of metabolic syndrome.

Ninety Sixth-Hour Impact of Scalding Burns on End Organ Damage, Systemic Oxidative Stress, and Wound Healing in Rats Treated With Three Different Types of Dressings

In this study, we investigated the effects of 3 different burn dressing treatments, including experimental, silver, and modern dressing materials, on systemic oxidative stress in rats with severe scald burns within the first 96 h. The rats were divided into five groups: a burn group (n = 10), a polylactic membrane group (n = 10), a silver sulfadiazine group (n = 10), a curcumin group (n = 10), and a control group (n = 10), consisting of equal numbers of female and male rats. In the first 4 groups, 30% of the rats' total body surface area was scalded at 95°C. The burn group was not treated. Each group was treated with group-name dressing material. The control group was neither treated nor burned. The rats were sacrificed, and blood and tissue samples were obtained at the 96th hour when severe effects of oxidative stress developed postburns. Systemic inflammatory biomarkers and oxidative stress parameters were examined. In addition, apoptosis and organ damage in liver, kidney, lung, and skin tissues were evaluated biochemically and histopathologically. When the parameters were statistically analyzed, we found that the systemic levels of oxidative stress and inflammatory damage to liver, kidney, and lung tissues were lower in the 3 treated groups than in the burn group. We believe that the dressing material's efficacy in the treatment of severe burns may be dependent on its ability to combat oxidative stress and inflammation.

Postnatal growth restriction alters myocardial mitochondrial energetics in mice

Postnatal growth restriction (PGR) can increase the risk of cardiovascular disease (CVD) potentially due to impairments in oxidative phosphorylation (OxPhos) within cardiomyocyte mitochondria. The purpose of this investigation was to determine if PGR impairs cardiac metabolism, specifically OxPhos. FVB (Friend Virus B-type) mice were fed a normal-protein (NP: 20% protein), or low-protein (LP: 8% protein) isocaloric diet 2 weeks before mating. LP dams produce ∼20% less milk, and pups nursed by LP dams experience reduced growth into adulthood as compared to pups nursed by NP dams. At birth (PN1), pups born to dams fed the NP diet were transferred to LP dams (PGR group) or a different NP dam (control group: CON). At weaning (PN21), all mice were fed the NP diet. At PN22 and PN80, mitochondria were isolated for respirometry (oxygen consumption rate,J O 2 ${J_{{{\mathrm{O}}_{\mathrm{2}}}}}$ ) and fluorimetry (reactive oxygen species emission,J H 2 O 2 ${J_{{{\mathrm{H}}_{\mathrm{2}}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) analysis measured as baseline respiration (LEAK) and with saturating ADP (OxPhos). Western blotting at PN22 and PN80 determined protein abundance of uncoupling protein 3, peroxiredoxin-6, voltage-dependent anion channel and adenine nucleotide translocator 1 to provide further insight into mitochondrial function. ANOVAs with the main effects of diet, sex and age with α-level of 0.05 was set a priori. Overall, PGR (7.8 ± 1.1) had significant (P = 0.01) reductions in respiratory control in complex I when compared to CON (8.9 ± 1.0). In general, our results show that PGR led to higher electron leakage in the form of free radical production and reactive oxygen species emission. No significant diet effects were found in protein abundance. The observed reduced respiratory control and increased ROS emission in PGR mice may increase risk for CVD in mice.

Assessment of liver function by gadoxetic acid avidity in MRI in a model of rapid liver regeneration in rats

BACKGROUND

This animal study investigates the hypothesis of an immature liver growth following ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) by measuring liver volume and function using gadoxetic acid avidity in magnetic resonance imaging (MRI) in models of ALPPS, major liver resection (LR) and portal vein ligation (PVL).

METHODS

Wistar rats were randomly allocated to ALPPS, LR or PVL. In contrast-enhanced MRI scans with gadoxetic acid (Primovist®), liver volume and function of the right median lobe (=future liver remnant, FLR) and the deportalized lobes (DPL) were assessed until post-operative day (POD) 5. Liver functionFLR/DPL was defined as the inverse value of time from injection of gadoxetic acid to the blood pool-corrected maximum signal intensityFLR/DPL multiplied by the volumeFLR/DPL.

RESULTS

In ALPPS (n = 6), LR (n = 6) and PVL (n = 6), volumeFLR and functionFLR increased proportionally, except on POD 1. Thereafter, functionFLR exceeded volumeFLR increase in LR and ALPPS, but not in PVL. Total liver function was significantly reduced after LR until POD 3, but never undercuts 60% of its pre-operative value following ALPPS and PVL.

DISCUSSION

This study shows for the first time that functional increase is proportional to volume increase in ALPPS using gadoxetic acid avidity in MRI.

Cutaneous burn injury represents a major risk factor for the development of traumatic ectopic bone formation following blast-related extremity injury

Blast-related traumatic heterotopic ossification (tHO) impacts clinical outcomes in combat-injured patients, leading to delayed wound healing, inflammatory complications, and reduced quality of life. Blast injured patients often have significant burns. This study investigated whether a partial thickness thermal burn injury exacerbates blast-related tHO in a clinically relevant polytrauma animal model. Adult male Sprague Dawley rats were subjected to an established model involving a whole-body blast overpressure exposure (BOP), complex extremity trauma followed by hind limb amputation (CET) followed by the addition of a 10 % total body surface area (TBSA) second degree thermal burn (BU). Micro-CT scans on post-operative day 56 showed a significant increase in HO volume in the CET + BU as compared to the CET alone injury group (p < .0001; 22.83 ± 3.41 mm3 vs 4.84 ± 5.77 mm3). Additionally, CET + BU concomitant with BOP significantly increased HO (p < .0001; 34.95 ± 7.71 mm3) as compared to CET + BU alone, confirming BOP has a further synergistic effect. No HO was detectable in rats in the absence of CET. Serum analysis revealed similar significant elevated (p < .0001) levels of pro-inflammatory markers (Cxcl1 and Il6) at 6 h post-injury (hpi) in the CET + BU and BOP + CET + BU injury groups as compared to naïve baseline values. Real-time qPCR demonstrated similar levels of chondrogenic and osteogenic gene expression in muscle tissue at the site of injury at 168 hpi in both the CET + BU and BOP+CET + BU injury groups. These results support the hypothesis that a 10 % TBSA thermal burn markedly enhances tHO following acute musculoskeletal extremity injury in the presence and absence of blast overpressure. Furthermore, the influence of BOP on tHO cannot be accounted for either in regards to systemic inflammation induced from remote injury or inflammatory-osteo-chondrogenic expression changes local to the musculoskeletal trauma, suggesting that another mechanism beyond BOP and BU synergistic effects are at play. Therefore, these findings warrant future investigations to explore other mechanisms by which blast and burn influence tHO, and testing prophylactic measures to mitigate the local and systemic inflammatory effects of these injuries on development of HO.

Perfusion Analysis Using High-Definition Indocyanine Green Angiography in Burn Comb Model

Indocyanine green angiography (ICGA) has been widely employed for quantitative evaluation of the rat comb burn model, but the imaging equipment, imaging protocol, and fluorescence data interpretation of ICGA remain unsatisfactory. This study aims to provide better solutions for the application of ICGA in perfusion analysis. The rat comb burn model was established under a series of different comb contact durations, including 10, 20, 25, 30, 35, and 40 s. Indocyanine green angiography was used to analyze wound perfusion. In total, 16 rats were divided into ibuprofen and control groups for the burn model, and their perfusion was compared. A total of 16 identical models were divided into standard- and high-dose indocyanine green (ICG) groups, and ICGA was conducted to investigate the dynamic change in wound fluorescence. Escharectomy was performed under real-time fluorescence mapping and navigation. The results showed that a comb contact duration of 30 s was optimum for the burn model. Indocyanine green angiography could accurately evaluate the histologically determined depth of thermal injury and wound perfusion in the rat comb model. Digital subtraction of residual fluorescence was necessary for multiple comparisons of perfusion. Dynamic changes in fluorescence and necrotic tissues were observed more clearly by high-dose (0.5 mg/kg) ICG in angiography. In conclusion, perfusion analysis by ICGA can be used to assess the histologically determined depth of thermal injury and the impact of a specific treatment on wound perfusion. Indocyanine green angiography can help to identify necrotic tissue. The above findings and related imaging protocols lay the foundation for future research.

Long-term effects of chronic exposure to electronic cigarette aerosol on the cardiovascular and pulmonary system in mice: A comparative study to cigarette smoke

Electronic cigarettes (e-cigarettes) have rapidly gained popularity as alternatives to traditional combustible cigarettes. However, their long-term health impact remains uncertain. This study aimed to investigate the effects of chronic exposure to e-cigarette aerosol (ECA) in mice compared to conventional cigarette smoke (CS) exposure. The mice were exposed to air (control), low, medium, or high doses of ECA, or a reference CS dose orally and nasally for eight months. Various cardiovascular and pulmonary assessments have been conducted to determine the biological and prosthetic effects. Histopathological analysis was used to determine structural changes in the heart and lungs. Biological markers associated with fibrosis, inflammation, and oxidative stress were investigated. Cardiac proteomic analysis was applied to reveal the shared and unique protein expression changes in ECA and CS groups, which related to processes such as immune activation, lipid metabolism, and intracellular transport. Overall, chronic exposure to ECA led to adverse cardiovascular and pulmonary effects in mice, although they were less pronounced than those of CS exposure. This study provides evidence that e-cigarettes may be less harmful than combustible cigarettes for the long-term health of the cardiovascular and respiratory systems in mice. However, further human studies are needed to clarify the long-term health risks associated with e-cigarette use.

Kinetics of Inflammatory Mediators in the Immune Response to Burn Injury: Systematic Review and Meta-Analysis of Animal Studies

Burns are often accompanied by a dysfunctional immune response, which can lead to systemic inflammation, shock, and excessive scarring. The objective of this study was to provide insight into inflammatory pathways associated with burn-related complications. Because detailed information on the various inflammatory mediators is scattered over individual studies, we systematically reviewed animal experimental data for all reported inflammatory mediators. Meta-analyses of 352 studies revealed a strong increase in cytokines, chemokines, and growth factors, particularly 19 mediators in blood and 12 in burn tissue. Temporal kinetics showed long-lasting surges of proinflammatory cytokines in blood and burn tissue. Significant time-dependent effects were seen for IL-1β, IL-6, TGF-β1, and CCL2. The response of anti-inflammatory mediators was limited. Burn technique had a profound impact on systemic response levels. Large burn size and scalds further increased systemic, but not local inflammation. Animal characteristics greatly affected inflammation, for example, IL-1β, IL-6, and TNF-α levels were highest in young, male rats. Time-dependent effects and dissimilarities in response demonstrate the importance of appropriate study design. Collectively, this review presents a general overview of the burn-induced immune response exposing inflammatory pathways that could be targeted through immunotherapy for burn patients and provides guidance for experimental set-ups to advance burn research.

Lung Protection After Severe Thermal Burns With Adenosine, Lidocaine, and Magnesium (ALM) Resuscitation and Importance of Shams in a Rat Model

The management of severe burns remains a complex challenge. Adenosine, lidocaine, and magnesium (ALM) resuscitation therapy has been shown to protect against hemorrhagic shock and traumatic injury. The aim of the present study was to investigate the early protective effects of small-volume ALM fluid resuscitation in a rat model of 30% total body surface area (TBSA) thermal injury. Male Sprague-Dawley rats (320-340 g; n = 25) were randomly assigned to: 1) Sham (surgical instrumentation and saline infusion, without burn, n = 5), 2) Saline resuscitation group (n = 10), or 3) ALM resuscitation group (n = 10). Treatments were initiated 15-min after burn trauma, including 0.7 mL/kg 3% NaCl ± ALM bolus and 0.25-0.5 mL/kg/h 0.9% NaCl ± ALM drip, with animals monitored to 8.25-hr post-burn. Hemodynamics, cardiac function, blood chemistry, hematology, endothelial injury markers and histopathology were assessed. Survival was 100% for Shams and 90% for both ALM and Saline groups. Shams underwent significant physiological, immune and hematological changes over time as a result of surgical traums. ALM significantly reduced malondialdehyde levels in the lungs compared to Saline (P = .023), and showed minimal alveolar destruction and inflammatory cell infiltration (P < .001). ALM also improved cardiac function and oxygen delivery (21%, P = .418 vs Saline), reduced gut injury (P < .001 vs Saline), and increased plasma adiponectin (P < .001 vs baseline). Circulating levels of the acute phase protein alpha 1-acid glycoprotein (AGP) increased 1.6-times (P < .001), which may have impacted ALM's therapeutic efficacy. We conclude that small-volume ALM therapy significantly reduced lung oxidative stress and preserved alveolar integrity following severe burn trauma. Further studies are required to assess higher ALM doses with longer monitoring periods.

Influence of Slco2b1-knockout and SLCO2B1-humanization on coproporphyrin I and III levels in rats

BACKGROUND AND PURPOSE

Coproporphyrin (CP) I and III are byproducts of haem synthesis currently investigated as biomarkers for drug-drug interactions involving hepatic organic anion transporting polypeptide (OATP) 1B transporters. Another hepatically expressed OATP-member is OATP2B1. The aim of this study was to test the impact of OATP2B1, which specifically transports CPIII, on CP serum levels, applying novel rat models.

EXPERIMENTAL APPROACH

CPIII transport kinetics and the interplay between OATP2B1 and multidrug resistance-associated proteins (MRPs) were determined in vitro using the vTF7 expression system. Novel rSlco2b1-/- and SLCO2B1+/+ rat models were characterized for physiological parameters and for CP serum levels. Hepatic and renal expression of transporters involved in CP disposition were determined by real-time qPCR, Western blot analysis, and immunohistochemistry.

KEY RESULTS

In vitro experiments revealed differences in transport kinetics comparing human and rat OATP2B1 and showed a consistent, species-specific interplay with hMRP3/rMRP3. Deletion of rOATP2B1 was associated with a trend towards lower CPI serum levels compared with wildtype rats, while CPIII remained unchanged. Comparing SLCO2B1+/+ with knockout rats revealed an effect of sex: only in females the genetic modification influenced CP serum levels. Analysis of hepatic and renal transporters revealed marginal, but in part, statistically significant differences in rMRP2 abundance, which may contribute to the observed changes in CP serum levels.

CONCLUSION AND IMPLICATIONS

Our findings support that factors other than OATP1B transporters are of relevance for basal CP levels. Only in female rats, humanization of SLCO2B1 affects basal CPI and CPIII serum levels, despite isomer selectivity of OATP2B1.

Traumatic brain injury extending to the striatum alters autonomic thermoregulation and hypothalamic monoamines in recovering rats

The brain cortex is the structure that is typically injured in traumatic brain injury (TBI) and is anatomically connected with other brain regions, including the striatum and hypothalamus, which are associated in part with motor function and the regulation of body temperature, respectively. We investigated whether a TBI extending to the striatum could affect peripheral and core temperatures as an indicator of autonomic thermoregulatory function. Moreover, it is unknown whether thermal modulation is accompanied by hypothalamic and cortical monoamine changes in rats with motor function recovery. The animals were allocated into three groups: the sham group (sham), a TBI group with a cortical contusion alone (TBI alone), and a TBI group with an injury extending to the dorsal striatum (TBI + striatal injury). Body temperature and motor deficits were evaluated for 20 days post-injury. On the 3rd and 20th days, rats were euthanized to measure the serotonin (5-HT), noradrenaline (NA), and dopamine (DA) levels using high-performance liquid chromatography (HPLC). We observed that TBI with an injury extending to the dorsal striatum increased core and peripheral temperatures. These changes were accompanied by a sustained motor deficit lasting for 14 days. Furthermore, there were notable increases in NA and 5-HT levels in the brain cortex and hypothalamus both 3 and 20 days after injury. In contrast, rats with TBI alone showed no changes in peripheral temperatures and achieved motor function recovery by the 7th day post-injury. In conclusion, our results suggest that TBI with an injury extending to the dorsal striatum elevates both core and peripheral temperatures, causing a delay in functional recovery and increasing hypothalamic monoamine levels. The aftereffects can be attributed to the injury site and changes to the autonomic thermoregulatory functions.

Investigation of the mechanism of tanshinone IIA to improve cognitive function via synaptic plasticity in epileptic rats

CONTEXT

Tanshinone IIA is an extract of Salvia miltiorrhiza Bunge (Labiatae) used to treat cardiovascular disorders. It shows potential anticonvulsant and cognition-protective properties.

OBJECTIVE

We investigated the mechanism of tanshinone IIA on antiepileptic and cognition-protective effects in the model of epileptic rats.

MATERIALS AND METHODS

Lithium chloride (LiCl)-pilocarpine-induced epileptic Wistar rats were randomly assigned to the following groups (n = 12): control (blank), model, sodium valproate (VPA, 189 mg/kg/d, positive control), tanshinone IIA low dose (TS IIA-L, 10 mg/kg/d), medium dose (TS IIA-M, 20 mg/kg/d) and high dose (TS IIA-H, 30 mg/kg/d). Then, epileptic behavioural observations, Morris water maze test, Timm staining, transmission electron microscopy, immunofluorescence staining, western blotting and RT-qPCR were measured.

RESULTS

Compared with the model group, tanshinone IIA reduced the frequency and severity of seizures, improved cognitive impairment, and inhibited hippocampal mossy fibre sprouting score (TS IIA-M 1.50 ± 0.22, TS IIA-H 1.17 ± 0.31 vs. model 2.83 ± 0.31), as well as improved the ultrastructural disorder. Tanshinone IIA increased levels of synapse-associated proteins synaptophysin (SYN) and postsynaptic dense substance 95 (PSD-95) (SYN: TS IIA 28.82 ± 2.51, 33.18 ± 2.89, 37.29 ± 1.69 vs. model 20.23 ± 3.96; PSD-95: TS IIA 23.10 ± 0.91, 26.82 ± 1.41, 27.00 ± 0.80 vs. model 18.28 ± 1.01).

DISCUSSION AND CONCLUSIONS

Tanshinone IIA shows antiepileptic and cognitive function-improving effects, primarily via regulating synaptic plasticity. This research generates a theoretical foundation for future research on potential clinical applications for tanshinone IIA.

Skeletal muscle wasting after burn is regulated by a decrease in anabolic signaling in the early flow phase

Following burns a sustained catabolic stress response is activated, resulting in skeletal muscle wasting. A better understanding of the underlying mechanisms of postburn skeletal muscle wasting is essential for the development of preventive and/or therapeutic strategies. Six weeks old female rats underwent a sham, 10% or 40% total body surface area scald burn. Ten days post-injury, severely burned animals gained significantly less weight compared to sham treated and minor burned animals, reflected in a significantly lower ratio of muscle to total body weight for Soleus (SOL) and Extensor Digitorum Longus (EDL) in the severely burned group. Postburn, total fiber number was significantly lower in EDL, while in SOL the amount of type1 fibers significantly increased and type2 fibers significantly decreased. No signs of mitochondrial dysfunction (COX/SDH) or apoptosis (caspase-3) were found. In SOL and EDL, eEF2 and pAKT expression was significantly lower after severe burn. MURF1,2,3 and Atrogin-1 was significantly higher in SOL, whilst in EDL MURF1,2,3 was significantly lower postburn. In both muscles, FOXO3A was significantly lower postburn. This study identified postburn changes in muscle anthropomorphology and proteins involved in pathways regulating protein synthesis and breakdown, with more pronounced catabolic effects in SOL.

Rational Design and Efficacy of Glucose-Responsive Insulin Therapeutics and Insulin Delivery Systems by Computation Using Connected Human and Rodent Models

Glucose-responsive insulins (GRIs) use plasma glucose levels in a diabetic patient to activate a specifically designed insulin analogue to a more potent state in real time. Alternatively, some GRI concepts use glucose-mediated release or injection of insulin into the bloodstream. GRIs hold promise to exhibit much improved pharmacological control of the plasma glucose concentration, particularly for the problem of therapeutically induced hypoglycemia. Several innovative GRI schemes are introduced into the literature, but there remains a dearth of quantitative analysis to aid the development and optimization of these constructs into effective therapeutics. This work evaluates several classes of GRIs that are proposed using a pharmacokinetic model as previously described, PAMERAH, simulating the glucoregulatory system of humans and rodents. GRI concepts are grouped into three mechanistic classes: 1) intrinsic GRIs, 2) glucose-responsive particles, and 3) glucose-responsive devices. Each class is analyzed for optimal designs that maintain glucose levels within the euglycemic range. These derived GRI parameter spaces are then compared between rodents and humans, providing the differences in clinical translation success for each candidate. This work demonstrates a computational framework to evaluate the potential clinical translatability of existing glucose-responsive systems, providing a useful approach for future GRI development.

Konjac Glucomannan Counteracted the Side Effects of Excessive Exercise on Gut Microbiome, Endurance, and Strength in an Overtraining Mice Model

Excessive exercise without adequate rest can lead to overtraining syndrome, which manifests a series of side effects, including fatigue, gut dysbiosis, and decremental sports performance. Konjac glucomannan (KGM) is a plant polysaccharide with numerous health-improving effects, but few studies reported its effects on the gut microbiome, endurance, and strength in an overtraining model. This study assessed the effect of KGM on gut microbiome, endurance, and strength in mice with excessive exercise. Three doses of KGM (1.25, 2.50, and 5.00 mg/mL) were administrated in drinking water to mice during 42 days of a treadmill overtraining program. The results showed that excessive exercise induced a significant microbial shift compared with the control group, while a high dose (5.00 mg/mL) of KGM maintained the microbial composition. The proportion of Sutterella in feces was significantly increased in the excessive exercise group, while the moderate dose (2.50 mg/mL) of KGM dramatically increased the relative abundance of Lactobacillus and SCFA production in feces. Additionally, the moderate dose and high dose of KGM counteracted the negative effects of excessive exercise on strength or/and endurance (43.14% and 39.94% increase through a moderate dose of KGM, Bonferroni corrected p < 0.05, compared with the excessive exercise group). Therefore, it suggests that KGM could prevent overtraining and improve sports performance in animal models.

Inhalation of electronic cigarettes slightly affects lung function and inflammation in mice

Electronic cigarettes have become increasingly popular, but the results of previous studies on electronic cigarette exposure in animals have been equivocal. This study aimed to evaluate the effects of electronic cigarette smoke (ECS) and cigarette smoke (CS) on lung function and pulmonary inflammation in mice to investigate whether electronic cigarettes are safer when compared to cigarettes. 32 specific pathogen-free BALB/c male mice were randomly grouped and exposed to fresh air (control), mint-flavored ECS (ECS1, 6 mg/kg), cheese-flavored ECS (ECS2, 6 mg/kg), and CS (6 mg/kg). After 3 weeks exposure to ECS or CS, we measured lung function (PIF and Penh) and blood oxygen saturation. The levels of TNF-α and IL-6 in the bronchoalveolar lavage fluid (BALF) and serum were measured using ELISA. HE staining was performed to observe the pathological changes in the lung tissues. The levels of IL-6 in BALF and serum, and TNF-α in BALF, were elevated similarly in the ECS and CS groups compared to the control group. Significant elevation was observed in serum TNF-α levels in the CS group. The total count of cells in BALF were increased after ECS1 exposure and CS exposure. PIF and oxygen saturation decreased, and Penh increased markedly in the CS group but not in the ECS groups. Compared with the ECS groups, mice in the CS group had widened lung tissue septa and increased inflammatory cell infiltration. However, we did not detect significant differences between mint-flavored and cheese-flavored e-cigarettes in our study. Overall, our findings suggested that both ECS and CS impair lung function and histopathology while promoting inflammation. In contrast, ECS has a less negative impact than CS.

Pretreatment with tadalafil attenuates cardiotoxicity induced by combretastatin A4 disodium phosphate in rats

Combretastatin A4 disodium phosphate (CA4DP) is a prodrug of combretastatin A4 (CA4), a microtubule-disassembling agent that exhibits antitumor effects by inhibiting tumor cell proliferation and inducing morphological changes and apoptosis in vascular endothelial cells in tumors. However, cardiotoxicity induced by ischemia and hypertension is a severe adverse event. In this study, we focused on the fact that phosphodiesterase (PDE) 5 inhibitors dilate the heart and peripheral blood vessels and aimed to investigate whether co-administration of tadalafil, a PDE5 inhibitor, can attenuate cardiotoxicity without altering the antitumor effect of CA4DP. To investigate cardiotoxicity, CA4DP and/or tadalafil were administered to rats, and blood pressure, echocardiography, histopathology, and cGMP concentration in the myocardium were examined. Administration of CA4DP increased systolic blood pressure, decreased cardiac function, lowered cGMP levels in the myocardium, and led to necrosis of myocardial cells. Co-administration of tadalafil attenuated these CA4DP-induced changes. To investigate the antitumor effect, canine mammary carcinoma cell lines (CHMp-13a) and human umbilical vein endothelial cells were cultured with CA4 and/or tadalafil, and cell proliferation and endothelial vascular tube disruption were examined. CHMp-13a cells were transplanted into nude mice and treated with CA4DP and/or tadalafil. CA4-induced inhibition of cell proliferation and disruption of the endothelial vascular tube were not affected by co-treatment with tadalafil, and the antitumor effects of CA4DP in xenograft mice were not reduced by co-administration of tadalafil. These results revealed that myocardial damage induced by CA4DP was attenuated by co-administration of tadalafil while maintaining antitumor efficacy.

Acute muscle mass loss was alleviated with HMGB1 neutralizing antibody treatment in severe burned rats

Burn injury is associated with muscle wasting, though the involved signaling mechanisms are not well understood. In this study, we aimed to examine the role of high mobility group box 1 (HMGB1) in signaling hyper-inflammation and consequent skeletal muscle impairment after burn. Sprague Dawley rats were randomly assigned into three groups: (1) sham burn, (2) burn, (3) burn/treatment. Animals in group 2 and group 3 received scald burn on 30% of total body surface area (TBSA) and immediately treated with chicken IgY and anti-HMGB1 antibody, respectively. Muscle tissues and other samples were collected at 3-days after burn. Body mass and wet/dry weights of the hind limb muscles (total and individually) were substantially decreased in burn rats. Acute burn provoked the mitochondrial stress and cell death and enhanced the protein ubiquitination and LC3A/B levels that are involved in protein degradation in muscle tissues. Further, an increase in muscle inflammatory infiltrate associated with increased differentiation, maturation and proinflammatory activation of bone marrow myeloid cells and αβ CD4+ T and γδ T lymphocytes was noted in in circulation and spleen of burn rats. Treatment with one dose of HMGB1 neutralizing antibody reduced the burn wound size and preserved the wet/dry weights of the hind limb muscles associated with a control in the markers of cell death and autophagy pathways in burn rats. Further, anti-HMGB1 antibody inhibited the myeloid and T cells inflammatory activation and subsequent dysregulated inflammatory infiltrate in the muscle tissues of burn rats. We conclude that neutralization of HMGB1-dependent proteolytic and inflammatory responses has potential beneficial effects in preventing the muscle loss after severe burn injury.

Transcriptomics, metabolomics, and in-silico drug predictions for liver damage in young and aged burn victims

Burn induces a systemic response affecting multiple organs, including the liver. Since the liver plays a critical role in metabolic, inflammatory, and immune events, a patient with impaired liver often exhibits poor outcomes. The mortality rate after burns in the elderly population is higher than in any other age group, and studies show that the liver of aged animals is more susceptible to injury after burns. Understanding the aged-specific liver response to burns is fundamental to improving health care. Furthermore, no liver-specific therapy exists to treat burn-induced liver damage highlighting a critical gap in burn injury therapeutics. In this study, we analyzed transcriptomics and metabolomics data from the liver of young and aged mice to identify mechanistic pathways and in-silico predict therapeutic targets to prevent or reverse burn-induced liver damage. Our study highlights pathway interactions and master regulators that underlie the differential liver response to burn injury in young and aged animals.

Light, Water, and Melatonin: The Synergistic Regulation of Phase Separation in Dementia

The swift rise in acceptance of molecular principles defining phase separation by a broad array of scientific disciplines is shadowed by increasing discoveries linking phase separation to pathological aggregations associated with numerous neurodegenerative disorders, including Alzheimer’s disease, that contribute to dementia. Phase separation is powered by multivalent macromolecular interactions. Importantly, the release of water molecules from protein hydration shells into bulk creates entropic gains that promote phase separation and the subsequent generation of insoluble cytotoxic aggregates that drive healthy brain cells into diseased states. Higher viscosity in interfacial waters and limited hydration in interiors of biomolecular condensates facilitate phase separation. Light, water, and melatonin constitute an ancient synergy that ensures adequate protein hydration to prevent aberrant phase separation. The 670 nm visible red wavelength found in sunlight and employed in photobiomodulation reduces interfacial and mitochondrial matrix viscosity to enhance ATP production via increasing ATP synthase motor efficiency. Melatonin is a potent antioxidant that lowers viscosity to increase ATP by scavenging excess reactive oxygen species and free radicals. Reduced viscosity by light and melatonin elevates the availability of free water molecules that allow melatonin to adopt favorable conformations that enhance intrinsic features, including binding interactions with adenosine that reinforces the adenosine moiety effect of ATP responsible for preventing water removal that causes hydrophobic collapse and aggregation in phase separation. Precise recalibration of interspecies melatonin dosages that account for differences in metabolic rates and bioavailability will ensure the efficacious reinstatement of the once-powerful ancient synergy between light, water, and melatonin in a modern world.

Synthesis and Characterization of Zinc Oxide Nanoparticles Stabilized with Biopolymers for Application in Wound-Healing Mixed Gels

A method for the synthesis of ZnO nanoparticles (ZnO NPs) gels was developed. ZnO NPs were obtained through a sol-gel method with zinc acetate usage as a precursor. Optimization of the method of synthesis of ZnO NPs gel has been carried out. It was observed that the most stable ZnO NPs gels are formed at room temperature, pH = 8 and molar concentration of zinc C(Zn²⁺) = 0.05-0.2 M. It was shown that the addition of polysaccharide significantly affects the rheological properties and microstructure of ZnO NPs gels. We found that the optimal polysaccharide for the synthesis of ZnO NPs gels is hydroxyethyl cellulose. It is shown that the microstructure of a gel of ZnO NPs stabilized with hydroxyethyl cellulose is represented by irregularly shaped particles that are assembled into aggregates, with sizes ranging from 150 to 1400 nm. A significant hysteresis region is observed in a gel of ZnO NPs stabilized with hydroxyethyl cellulose. The process of interaction of ZnO NPs with polysaccharides was investigated. It was shown that the interaction of ZnO NPs with polysaccharides occurs through a charged hydroxyl group. In the experiment, a sample of a gel of ZnO NPs modified with hydroxyethyl cellulose was tested. It was shown that the gel of ZnO NPs modified with hydroxyethyl cellulose has a pronounced regenerative effect on burn wounds, which is significantly higher than that of the control group and the group treated with a gel of ZnO microparticles (MPs) and hydroxyethyl cellulose. It is also shown that the rate of healing of burn wounds in animals treated with gel of ZnO nanoparticles with hydroxyethyl cellulose (group 3) is 16.23% higher than in animals treated with gel of ZnO microparticles with hydroxyethyl cellulose (group 2), and 24.33% higher than in the control group treated with hydroxyethyl cellulose. The average rate of healing of burn wounds for the entire experimental period in experimental animals of group 3 is 1.26 and 1.54 times higher than in animals of group 2 and control group, respectively. An experimental study of a gel of ZnO NPs modified with hydroxyethyl cellulose has shown the effectiveness of its use in modeling the healing of skin wounds through primary tension.

Extensive Peritonectomy is an Independent Risk Factor for Cisplatin HIPEC-Induced Acute Kidney Injury

Background

Cisplatin (CDDP)-containing hyperthermic intraperitoneal chemotherapy (HIPEC) is frequently applied in selected patients with peritoneal malignancies derived from ovarian cancer, gastric cancer, and primary peritoneal mesothelioma. HIPEC with CDDP increases perioperative morbidity, in particular by inducing acute kidney injury (AKI). Factors contributing to occurrence of AKI after intraperitoneal perfusion with CDDP have not been sufficiently evaluated.

Patients and Methods

Data from 63 patients treated with a CDDP-containing HIPEC regimen were retrospectively analyzed concerning demographics, underlying disease, surgery, and HIPEC details to evaluate risk factors of AKI. A preclinical rat perfusion model was applied to assess the influence of temperature, concentration, perfusate volume, perfusion flow rate, and extent of peritonectomy on drug absorption upon intraperitoneal CDDP perfusion.

Results

AKI occurred in 66.1% of patients undergoing CDDP-containing HIPEC, with total intraoperative fluid influx being a negative and the extent of parietal peritonectomy being a positive independent predictor of postoperative AKI. In a preclinical model, bilateral anterior parietal peritonectomy significantly increased systemic CDDP absorption by 1.6 to 2-fold. CDDP plasma levels in animals were significantly higher after both perfusion with increased CDDP perfusate concentrations and bilateral anterior parietal peritonectomy.

Conclusion

CDDP-containing HIPEC is associated with relevant morbidity owing to its systemic toxicity. Extent of parietal peritonectomy is an independent predictor of AKI. CDDP dose reduction should be considered in case of extensive parietal peritonectomy. Cytostatic drug concentrations in HIPEC perfusate should be paid more attention to than total dose per body surface area. Further clinical studies are needed to confirm the presented preclinical findings.

Cardiac and respiratory muscle responses to dietary N-acetylcysteine in rats consuming a high-saturated fat, high-sucrose diet

NEW FINDINGS

What is the central question of this study? This study addresses whether a high-fat, high-sucrose diet causes cardiac and diaphragm muscle abnormalities in male rats and whether supplementation with the antioxidant N-acetylcysteine reverses diet-induced dysfunction. What is the main finding and its importance? N-Acetylcysteine attenuated the effects of high-fat, high-sucrose diet on markers of cardiac hypertrophy and diastolic dysfunction, but neither high-fat, high-sucrose diet nor N-acetylcysteine affected the diaphragm. These results support the use of N-acetylcysteine to attenuate cardiovascular dysfunction induced by a 'Western' diet.

ABSTRACT

Individuals with overweight or obesity display respiratory and cardiovascular dysfunction, and oxidative stress is a causative factor in the general aetiology of obesity and of skeletal and cardiac muscle pathology. Thus, this preclinical study aimed to define diaphragmatic and cardiac morphological and functional alterations in response to an obesogenic diet in rats and the therapeutic potential of an antioxidant supplement, N-acetylcysteine (NAC). Young male Wistar rats consumed ad libitum a 'lean' or high-saturated fat, high-sucrose (HFHS) diet for ∼22 weeks and were randomized to control or NAC (2 mg/ml in the drinking water) for the last 8 weeks of the dietary intervention. We then evaluated diaphragmatic and cardiac morphology and function. Neither HFHS diet nor NAC supplementation affected diaphragm-specific force, peak power or morphology. Right ventricular weight normalized to estimated body surface area, left ventricular fractional shortening and posterior wall maximal shortening velocity were higher in HFHS compared with lean control animals and not restored by NAC. In HFHS rats, the elevated deceleration rate of early transmitral diastolic velocity was prevented by NAC. Our data showed that the HFHS diet did not compromise diaphragmatic muscle morphology or in vitro function, suggesting other possible contributors to breathing abnormalities in obesity (e.g., abnormalities of neuromuscular transmission). However, the HFHS diet resulted in cardiac functional and morphological changes suggestive of hypercontractility and diastolic dysfunction. Supplementation with NAC did not affect diaphragm morphology or function but attenuated some of the cardiac abnormalities in the rats receiving the HFHS diet.

DiHuangYin decoction protects dopaminergic neurons in a Parkinson's disease model by alleviating peripheral inflammation

BACKGROUND

Parkinson's disease (PD) is a progressive neurodegenerative disease, which brings increasing threaten for human health and is still lacking of satisfied treatment. Recently, numerous studies have also demonstrated the effect of particular subsets of CD4+ T cells on PD pathology. Th17 cells played an important role in the pathogenesis of PD. Traditional Chinese medicine has been widely used to treat PD clinically, and has a tremendous potential in clinical drug development.

PURPOSE

The aim of this study was to verify the therapeutic effects of DHY on PD mice model, and investigate the underlying molecular mechanisms.

METHODS

Herein, we verified the effects of a traditional Chinese medicine formula, named DiHuangYin (DHY), on the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced mouse model of PD through behavioral and histopathological tests. High-resolution mass spectrometry combined with molecular networking was applied for substance profiling of DHY. Based on the chemical compositions of DHY, network pharmacology was performed. Immunofluorescence and ELISA were used to evaluate the expressions of cytokines in peripheral immune system. qPCR and immunofluorescence were used to detect the inflammation infiltration of central nervous system.

RESULTS

DHY improves the motor function and prevents the loss of dopaminergic neurons in the MPTP induced mouse model of PD. 118 components of DHY were identified or tentatively characterized based on the MS/MS data and molecular networking. Network pharmacology suggested IL-17 signaling pathway and neuroactive ligand-receptor interaction as the important targets. Compared to the MPTP-intoxicated mice, the DHY group showed a decreased number of Th17 cells from splenocytes and a decreased level of IL-17A in the serum. On the other hand, less inflammatory infiltration was found in the midbrain of DHY treatment mice which might be associated with the attenuated peripheral inflammation.

CONCLUSIONS

Though the underlying pharmacological mechanism of DHY is still lacking, we provided evidence that DHY decoction could protect dopaminergic neurons by mitigating peripheral inflammation.

Wound Healing Activity of 80% Methanolic Crude Extract and Solvent Fractions of the Leaves of Justicia schimperiana (Hochst. ex Nees) T. Anderson (Acanthaceae) in Mice

Introduction

Justicia schimperiana has been used traditionally for the treatment of wound and skin burn, but there is no scientific evidence that supports the traditional claim.

Objective

To evaluate the wound healing activity of 80% methanol crude extract and solvent fractions of the leaves of Justicia schimperiana in mice.

Methods

Mice were used for wound healing study, while rats were used for acute dermal toxicity test. The 80% methanol crude extract and chloroform, ethyl acetate and aqueous fractions were formulated in ointments with 5% and 10% strength. Burn, excision and incision wound models were used to evaluate the effect of the crude extract, whereas the activity of the solvent fractions was evaluated using excision wound model. Parameters such as wound contraction, and period of epithelialization were studied in the excision and burn wound models, while tensile strength was measured in incision wound model.

Results

Treatment of wound with 80% methanol extract of Justicia schimperiana leaves using 5% (w/w) and 10% (w/w) ointment formulation induced significant (P<0.05) improvement in wound contraction rate, epithelialization time and skin breaking strength in excision, incision and burn wound model, respectively as compared to negative control. The chloroform, ethyl acetate and aqueous fractions with 5% (w/w) and 10% (w/w) ointment formulation showed significant (p<0.001) improvement in wound contraction and epithelialization time in excision wound model as compared to the negative control group.

Conclusion

This study has demonstrated that the 80% methanol crude extract and solvent fractions of Justicia schimperiana leaves possess wound healing activity.

Short-term exposure to urban PM2.5 particles induces histopathological and inflammatory changes in the rat small intestine

Air pollution and exposure to fine airborne particles with aerodynamic diameter <2.5 μm (PM_2.5 ) negatively impacts human health. Airways constitute a primary route of exposure but PM_2.5 -contaminated food, drinks as well as mucociliary and hepatobiliary clearance all constitute potential entry points into the intestine. This study evaluated intestinal histopathological and inflammatory changes as well as enteric neuronal numbers after short- or long-term exposure to urban PM_2.5 . Using a nebulizer, male rats were exposed to a mist with a concentration of 5.3mg PM_2.5 /m³ for 8 h (short term) or 1.8 mg PM_2.5 /m³ for 3 h/day, 5 days/week for 8 weeks (long-term) with controls run in parallel. Samples were taken from three regions of the small intestine as well as the colon. Results showed that short-term exposure to PM_2.5 induces mucosal lesions and reduces IL1β levels in the small intestine but not colon. No significant changes were observed after long-term exposure, suggesting the presence of intestinal adaptation to environmental stressors in the PM_2.5 . To our knowledge, this is the first study to systematically characterize regional effects along the intestine.

Amnion bilayer for dressing and graft replacement for delayed grafting of full-thickness burns; A study in a rat model

Burn is a common case in developing countries, with over half of fire-related deaths reported in Southeast Asia and full-thickness burns as a high mortality risk. Human amnion has been used as a wound dressing for centuries. In this study, a decellularised amnion overlaid with fibrin, “amnion bilayer (AB),” was used as a dressing immediately after burn and as a graft to replace the scar in Sprague-Dawley rats subjected to full-thickness burn model. The aim was to observe whether amnion bilayer can reduce damages in third-grade burn when skin replacement is deemed impossible. The burn was induced using an electrical solder, heated for 5 mins, and contacted on the rat’s bare skin for 20 s. AB was applied as a (i) dressing immediately after induction and graft after eschar removal. Two groups (n = 6) were compared: AB and Sofra-Tulle ^®, the National Hospital of Indonesia (NHI) protocol. Sections were stained with hematoxylin and eosin and Masson trichrome stains. Immunohistochemistry labelling was used to indicate scars (α-smooth muscle actin [α-SMA] and collagen-1) and angiogenesis (von Willebrand factor). Also, the macrophages inflammatory protein-3α (MIP-3α) indicates an early inflammatory process. The post dressing of the AB group demonstrated hair follicle remains and adipose tissue development. The NHI group appeared with a denatured matrix. Complete healing was seen in the AB group after 28 days with skin appendages similar to normal, while the NHI group showed no appendages in the centre of the actively inflamed area. The α-SMA was found in both groups. Collagen-1 was highly expressed in the NHI group, which led to a scar. Angiogenesis was found more in the AB group. The AB group had shown the capacity to accelerate complete healing and recover skin appendages better than the current protocol.

The Effect of Udenafil on Stasis Zone in an Experimental Burn Model

BACKGROUND

Management of the burn injuries is still a problematic issue because the stasis zone may become necrotic. We hypothesized that udenafil, a potent phospodiesterase inhibitor, can be beneficial in burn treatment by enhancing the viability of the stasis zone.

METHODS

Fifteen Wistar rats were randomly divided into 3 groups. Comb burn injury model was conducted bilaterally on the back of rats in each subject. Group 1 received 1 mL/d of saline orally for 7 days. Group 2 received 10 mg/kg per day of udenafil for 7 days. Group 3 received 20 mg/kg per day of udenafil for 7 days. At the end of seventh day, gross morphological and histopathological samples of stasis zone survival were evaluated.

RESULTS

Histopathological examination of groups 2 and 3 revealed that the stasis zone was mostly viable. The mean necrotic area and severity of inflammation was significantly higher in the control group compared with the treatment groups. Significant differences were determined in treatment groups compared with control group in terms of vital stasis zone area and histopathological parameters.

CONCLUSIONS

Udenafil treatment improved tissue survival on zone of stasis in. Future experimental studies should be conducted to develop zone of stasis treatment protocols combining udenafil with potent anti-inflammatory and antioxidant drugs.

Chitosan self-assembled polymeric nanoparticles for percutaneous delivery of betamethasone in contact dermatitis

OBJECTIVE

The study was performed with an aim to investigate the efficiency of two treatment options in experimental nickel-induced contact dermatitis (CT), with either betamethasone or chitosan cross-linked nano-encapsulated betamethasone lanoline solutions (nano-betamethasone).

METHODS

Male Wistar rats were used. The differences were compared based on lesion visual appearance, skinfold thickness, white blood cell count (WBC), erythrocyte sedimentation rate (ESR), blood serum prooxidant-antioxidant balance (thiobarbituric acid reactive substances, TBARS; supersoxide dismutase, SOD; catalase, KAT), blood cytokine profile (TNF-α, IL-1β, IL-10, and IL-4), and histological examination of affected skin.

RESULTS

All animals treated with nickel sulfate developed CT and systemic inflammatory response on day 12, which only slightly lessened, if left untreated, on day 20. The therapeutic effectiveness of nano-betamethasone was significantly far superior (p < 0.01) compared to betamethasone. Specifically, the visual appearance of lesion severity of betamethasone vs. nano-betamethasone ± SD was 1.82 ± 0.18 vs. 1.17 ± 0.24 points, skinfold thickness-2.68 ± 0.12 vs. 2.12 ± 0.10 mm, ESR-6.38 ± 0.27 vs. 5.12 ± 0.20 mm/h, WBC-8.47 ± 0.28 vs. 7.17 ± 0.24 10⁹/L, TBARS-1.09 ± 0.04 vs. 0.94 ± 0.02 µmol/L, SOD-3.38 ± 0.26 vs. 4.12 ± 0.18 r.u./L, KAT-11.54 ± 0.14 vs. 10.02 ± 0.19 mkatal/L, respectively. The nano-betamethasone formulation was also more effective (p < 0.01) in increasing anti-inflammatory cytokines level, IL-10 (8.96 ± 0.32 vs. 7.54 ± 0.52 pg/mL) and IL-4 (13.16 ± 0.45 vs. 11.43 ± 0.58 pg/mL); and decreasing in pro-inflammatory TNF-α (20.94 ± 2.30 vs. 26.98 ± 1.16 pg/mL) and IL-1β (19.35 ± 1.28 vs. 24.77 ± 1.75 pg/mL), respectively. These findings were also supported with histological examination.

CONCLUSIONS

Nano-betamethasone may be considered as a more successful transcutaneous therapy for managing contact dermatitis compared to ointments consisting of betamethasone in traditional form.

The pharmacokinetics of PEGylated liposomal doxorubicin are not significantly affected by sex in rats or humans, but may be affected by immune dysfunction

PEGylated liposomal doxorubicin (PLD, Caelyx®, Doxil®) has been suggested to show significant sex-based differences in plasma clearance, as well as high inter-individual variability that may be driven by monocyte counts in cancer patients. This study aimed to establish if these differences are similarly observed in rats, which exhibit similar liposome clearance mechanisms to humans, and to use this model to identify sources of inter-individual and sex-based pharmacokinetic variability. The plasma and lymphatic pharmacokinetics of PLD were evaluated in male and female rats by quantifying doxorubicin as well as the ³H-labelled liposome. In general, the pharmacokinetics of doxorubicin and the ³H-liposome did not differ significantly between male and female rats when corrected for body surface area. Female rats did, however, show significantly higher doxorubicin concentrations in lymph compared to male rats. With the exception of serum testosterone concentrations in males, none of the physiological parameters evaluated correlated with plasma clearance. Further, reanalysis of published human data that formerly reported sex-differences in PLD plasma clearance similarly revealed no significant differences in PLD plasma clearance between males and females with solid tumours, but increased plasma clearance in patients with Kaposi's sarcoma (generally HIV+/immunocompromised). These data suggest that with the exception of lymphatic exposure, there are unlikely to be significant sex effects in the pharmacokinetics of liposomes, but immune function may contribute to inter individual variability.

TPPU treatment of burned mice dampens inflammation and generation of bioactive DHET which impairs neutrophil function

Oxylipins modulate the behavior of immune cells in inflammation. Soluble epoxide hydrolase (sEH) converts anti-inflammatory epoxyeicosatrienoic acid (EET) to dihydroxyeicosatrienoic acid (DHET). An sEH-inhibitor, TPPU, has been demonstrated to ameliorate lipopolysaccharide (LPS)- and sepsis-induced inflammation via EETs. The immunomodulatory role of DHET is not well characterized. We hypothesized that TPPU dampens inflammation and that sEH-derived DHET alters neutrophil functionality in burn induced inflammation. Outbred mice were treated with vehicle, TPPU or 14,15-DHET and immediately subjected to either sham or dorsal scald 28% total body surface area burn injury. After 6 and 24 h, interleukin 6 (IL-6) serum levels and neutrophil activation were analyzed. For in vitro analyses, bone marrow derived neutrophil functionality and mRNA expression were examined. In vivo, 14,15-DHET and IL-6 serum concentrations were decreased after burn injury with TPPU administration. In vitro, 14,15-DHET impaired neutrophil chemotaxis, acidification, CXCR1/CXCR2 expression and reactive oxygen species (ROS) production, the latter independent from p38MAPK and PI3K signaling. We conclude that TPPU administration decreases DHET post-burn. Furthermore, DHET downregulates key neutrophil immune functions and mRNA expression. Altogether, these data reveal that TPPU not only increases anti-inflammatory and inflammation resolving EET levels, but also prevents potential impairment of neutrophils by DHET in trauma.

Mechanical and Structural Remodeling of Cardiac Muscle after Aerobic and Resistance Exercise Training in Rats

INTRODUCTION

Aerobic and resistance exercise training results in distinct structural changes of the heart. The mechanics of how cardiac cells adapt to resistance training and the benefits to cells when combining aerobic and resistance exercise remains largely unknown. The purpose of this study was to compare mechanical adaptations of skinned cardiac fiber bundles after chronic resistance, aerobic and combined exercise training in rats. We hypothesized that differences in mechanical function on the fiber bundle level coincide with differences previously reported in the structure of the heart.

METHOD

Twelve-week-old rats were assigned to (i) an aerobic running group (n = 6), (ii) a ladder climbing resistance group (n = 6), (iii) a combination group subjected to aerobic and resistance training (n = 6), or (iv) a sedentary (control) group (n = 5). Echocardiography was used to measure cardiac structural remodeling. Skinned cardiac fiber bundles were used to determine active and passive force properties, maximal shortening velocity, and calcium sensitivity.

RESULTS

Aerobically trained animals had 43%-49% greater ventricular volume and myocardial thickness, and a 4%-17% greater shortening velocity and calcium sensitivity compared with control group rats. Resistance-trained rats had 37%-71% thicker ventricular walls, a 56% greater isometric force production, a 9% greater shortening velocity, and a 4% greater calcium sensitivity compared with control group rats. The combination exercise-trained rats had 25%-43% greater ventricular volume and myocardial wall thickness, a 55% greater active force production, a 7% greater shortening velocity, and a 60% greater cross-bridge cooperativity compared with control group rats.

CONCLUSIONS

The heart adapts differently to each exercise modality, and a combination of aerobic and resistance training may have the greatest benefit for cardiac health and performance.

N-Acetylcysteine Added to Local Anesthesia Reduces Scar Area and Width in Early Wound Healing-An Animal Model Study

The aim of the study was to evaluate if a pre-incisional N-acetylcysteine (NAC) treatment altered the process of wound healing in a rat model. The dorsal skin of 24 Sprague-Dawley rats was incised in six locations. Before the incisions were made, skin was injected either with lidocaine and epinephrine (one side) or with these agents supplemented with 0.015%, 0.03%, or 0.045% NAC (contralaterally). Photographic documentation of the wound healing process was made at 11 time points. Rats were sacrificed 3, 7, 14, or 60 days after incision to excise scars for histological analysis. They included: Abramov scale scoring, histomorphometry analysis, and collagen fiber arrangement assessment. Skin pretreated with 0.03% NAC produced the shortest scars at all analyzed time points, though this result was statistically insignificant. At this NAC concentration the scars had smaller areas on the third day and were narrower on the day 4 compared with all the other groups (p < 0.05). On day 7, at the same concentration of NAC, the scars had a higher superficial concentration index (p = 0.03) and larger dermal proliferation area (p = 0.04). NAC addition to pre-incisional anesthetic solution decreased wound size and width at an early stage of scar formation at all concentrations; however, with optimal results at 0.03% concentration.

Consuming oxidative frying oil impairs cardiac energy production and calcium recycling, causing cardiac hypertrophy, fibrosis and diastolic dysfunction in male Sprague Dawley rats

With regards to cardiovascular health, frequent consumption of fried foods is discouraged, despite a lack of clear evidence of a direct link between eating oxidative frying oil (OFO) and cardiovascular diseases. In this study, male Sprague Dawley rats were exposed to diets containing fresh or fried soybean oil (groups C and O, respectively) from in utero to 28 weeks of age. A subset of rats in group O was supplemented with vitamin E (500 mg/kg of DL-α-tocopherol acetate; group OE) from 8 week of age onward to mitigate oxidative stress associated with OFO ingestion. Echocardiography, cardiac histology and indices associated with ATP production and calcium cycling in cardiac tissues were measured. Compared to group C, there was cardiac hypertrophy, fibrosis and diastolic dysfunction, in groups O and OE, with no differences between the latter two groups. Although cardiac mRNA levels of genes associated with mitochondrial biogenesis and function were increased, there were lower ATP concentrations and higher transcripts of uncoupling proteins in groups O and OE than in group C. In addition, decreases in phosphorylation of phospholamban and Ca²⁺/calmodulin-dependent protein kinase II activity, plus increased protein phosphatase 2A activity in groups O and OE, implied calcium cycling required for cardiac function was disrupted by OFO consumption. We concluded that long-term OFO exposure resulted in cardiac hypertrophy, fibrosis and diastolic dysfunction that was not mitigated by vitamin E supplementation. Underlying mechanisms were partly attributed to inefficient energy production via uncoupled phosphorylation and disrupted calcium cycling.

Serial T1 mapping of right ventricle in pulmonary hypertension: comparison with histology in an animal study

BACKGROUND

Right ventricular (RV) free wall fibrosis is an important component of adverse remodeling with RV dysfunction in pulmonary hypertension (PH). However, no previous reports have compared cardiovascular magnetic resonance (CMR) findings and histological analysis for RV free wall fibrosis in PH. We aimed to assess the feasibility of CMR T1 mapping with extracellular volume fraction (ECV) for evaluating the progression of RV free wall fibrosis in PH, and compared imaging findings to histological collagen density through an animal study.

METHODS

Among 42 6-week-old Wistar male rats, 30 were classified according to disease duration (baseline before monocrotaline injection, and 2, 4, 6 and 8 weeks after injection) and 12 were used to control for aging (4 and 8 weeks after the baseline). We obtained pre and post-contrast T1 maps for native T1 and ECV of RV and left ventricular (LV) free wall for six animals in each disease-duration group. Collagen density of RV free wall was calculated with Masson's trichrome staining. The Kruskall-Wallis test was performed to compare the groups. Native T1 and ECV to collagen density were analyzed with Spearman's correlation.

RESULTS

The mean values of native T1, ECV and collagen density of the RV free wall at baseline were 1541 ± 33 ms, 17.2 ± 1.3%, and 4.7 ± 0.5%, respectively. The values of RV free wall did not differ according to aging (P = 0.244, 0.504 and 0.331, respectively). However, the values significantly increased according to disease duration (P < 0.001 for all). Significant correlations were observed between native T1 and collagen density (r = 0.770, P < 0.001), and between ECV and collagen density for the RV free wall (r = 0.815, P < 0.001) in PH. However, there was no significant difference in native T1 and ECV values for the LV free wall according to the disease duration from the baseline (P = 0.349 and 0.240, respectively).

CONCLUSIONS

We observed significantly increased values for native T1 and ECV of the RV free wall without significant increase of the LV free wall according to the disease duration of PH, and findings were well correlated with histological collagen density.

Effect of folinic acid on serum homocysteine, TNFα, IL-10, and HMGB1 gene expression in head injury model

Background

Head injury or traumatic brain injury is the leading cause of mortality and morbidity. Many modalities of neuroprotection had been developed in brain injury but there was no much information regarding folinic acid's effect on neuroinflammation associated with homocysteine, TNFα, IL-10, and HMGB1.

Objective

This study aimed to investigate whether folinic acid has improving effect on head injury model.

Method

This study was done in the rat's head injury model using modified Marmarou weight drop model. Fifteen rats were randomized and grouped into 3 groups: Group A: Folinic acid (+), head injury (−); Group B: Folinic acid (−), head injury (+); Group C: Folinic acid (+), head injury (+). Folinic acid was administered intraperitoneally with a dose of 60 mg/m². Blood samples were taken immediately after head injury (H0), 12 h (H12), and 24 h (H24) after head injury from the lateral vein of tail. Serum level of homocysteine, TNFα, and IL-10 were measured using ELISA, and HMGB1 gene expression was measured with Real-Time RT-PCR.

Results

This study found serum level of homocysteine, TNFα, IL-10 and HMGB1 gene expression were markedly increased at all time points after head injury. Significantly lower level of serum homocysteine, TNFα, IL-10 and HMGB1 gene expression were found after 24 h treatment with folinic acid in group C compared to those in group B.

Conclusion

Folinic acid may have anti-inflammatory properties in traumatic brain injury by inhibition of serum level of homocysteine, TNFα, IL-10 and HMGB1 gene expression.

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An animal study of head injury model using modified Marmarou weight drop model.

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This three groups study with folinic acid treatment on head injury rats.

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Folinic acid has anti-inflammatory properties in traumatic brain injury model.

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Folinic acid inhibits serum level of homocysteine, TNFα, IL-10 and HMGB1expression.