Propionyl-L-Carnitine Enhances Wound Healing and Counteracts Microvascular Endothelial Cell Dysfunction

Forkhead box A1 induces angiogenesis through activation of the S100A8/p38 MAPK axis in cutaneous wound healing

BACKGROUND

The association between S100 calcium-binding protein A8 (S100A8) and angiogenesis has been reported in previous reports. This study focuses on the roles of S100A8 in the angiogenesis of human dermal microvascular endothelial cells (HDMECs) and in cutaneous wound healing in mice.

METHODS

Candidate genes related to angiogenesis activity were screened using a GSE83582 dataset. The overexpression DNA plasmid of S100A8 was transfected into HDMECs to analyze its effect on cell proliferation, migration, and angiogenesis. Full-thickness skin wounds were induced on mice, followed by adenovirus treatments to analyze the function of gene alteration in wound healing and pathological changes. The upstream regulator of S100A8 was predicted by bioinformatics analysis and verified by luciferase and immunoprecipitation assays. The role of the forkhead box A1 (FOXA1)-S100A8 interaction in p38 MAPK activation and angiogenesis were validated by rescue experiments.

RESULTS

S100A8 was identified as a gene significantly correlated with angiogenesis. The S100A8 upregulation promoted the proliferation, migration, and angiogenesis of HDMECs, and it promoted p38 MAPK phosphorylation. Treatment of SB203580, a p38 MAPK inhibitor, blocked the promoting effect of S100A8. FOXA1 was identified as an upstream factor of S100A8 promoting its transcription. FOXA1 overexpression in HDMECs increased p38 MAPK phosphorylation and enhanced the activity of cells, which were blocked by the S100A8 inhibition. Similar results were reproduced in vivo where FOXA1 overexpression accelerated whereas the S100A8 knockdown retarded the cutaneous wound healing in mice.

CONCLUSION

FOXA1 mediates the phosphorylation of p38 MAPK through transcription activation of S100A8, thereby inducing angiogenesis and promoting cutaneous wound healing.

Metabolic Profiling Reveals Changes in Serum Predictive of Venous Ulcer Healing

OBJECTIVE

The aim of this study was to identify potential biomarkers predictive of healing or failure to heal in a population with venous leg ulceration.

SUMMARY BACKGROUND DATA

Venous leg ulceration presents important physical, psychological, social and financial burdens. Compression therapy is the main treatment, but it can be painful and time-consuming, with significant recurrence rates. The identification of a reliable biochemical signature with the ability to identify nonhealing ulcers has important translational applications for disease prognostication, personalized health care and the development of novel therapies.

METHODS

Twenty-eight patients were assessed at baseline and at 20 weeks. Untargeted metabolic profiling was performed on urine, serum, and ulcer fluid, using mass spectrometry and nuclear magnetic resonance spectroscopy.

RESULTS

A differential metabolic phenotype was identified in healing (n = 15) compared to nonhealing (n = 13) venous leg ulcer patients. Analysis of the assigned metabolites found ceramide and carnitine metabolism to be relevant pathways. In this pilot study, only serum biofluids could differentiate between healing and nonhealing patients. The ratio of carnitine to ceramide was able to differentiate between healing phenotypes with 100% sensitivity, 79% specificity, and 91% accuracy.

CONCLUSIONS

This study reports a metabolic signature predictive of healing in venous leg ulceration and presents potential translational applications for disease prognostication and development of targeted therapies.

The antidepressant effects and serum metabonomics of bifid triple viable capsule in a rat model of chronic unpredictable mild stress

Background

Probiotics have shown potential antidepressant effects. This study evaluated the effect and probable mechanisms of bifid triple viable capsules (BTVCs) on a rat model of chronic unpredictable mild stress (CUMS).

Materials and methods

Rats were randomly divided into Normal, CUMS model, fluoxetine hydrochloride (FLX), BTVCs, and FLX+BTVCs groups. Depressive-like behaviours, pathological changes in the hippocampus, changes in serum metabolites and potential biomarkers, and metabolic pathways were detected via behavioural tests, haematoxylin-eosin staining, nissl staining, non-targetted metabolomics, and ingenuity pathway analysis (IPA).

Results

The rats displayed depressive-like behaviours after CUMS exposure, but BTVCs ameliorated the depressive-like behaviours. In addition, the pathological results showed that the hippocampal tissue was damaged in rats after CUMS exposure and that the damage was effectively alleviated by treatment with BTVCs. A total of 20 potential biomarkers were identified. Treatment with BTVCs regulated D-phenylalanine, methoxyeugenol, (±)-myristoylcarnitine, 18:3 (6Z, 9Z, 12Z) /P-18:1 (11Z), propionyl-L-carnitine, and arachidonic acid (AA) concentrations, all compounds that are involved with biosynthesis of unsaturated fatty acids, glycerophospholipid metabolism, linoleic acid metabolism and AA metabolism. The IPA demonstrated that endothelin-1 signalling and cyclic adenosine monophosphate response element binding protein (CREB) signalling in neurons may be involved in the development of depression.

Conclusion

Our findings suggest that BTVCs can alleviate depressive-like behaviours, restore damage to the hippocampus in CUMS rats and regulate serum metabolism, which may be related to endothelin-1 signalling or CREB signalling in neurons.

Common, But Neglected: A Comprehensive Review of Leg Ulcers in Sickle Cell Disease

OBJECTIVE

To compile available evidence to better understand the management of leg ulcers in sickle cell disease (SCD), as well as describe potential therapeutic steps that may be required to improve the quality of life of patients with SCD leg ulcers.

DATA SOURCES

MEDLINE, PubMed, EMBASE, and Web of Science databases.

STUDY SELECTION

A comprehensive search was conducted to retrieve relevant studies using the keywords "sickle cell disease and leg ulcer," "ulcer treatments, diagnosis and sickle cell," and "wound sickle cell." Studies published through July 2020 were included.

DATA EXTRACTION

Two independent authors selected all studies that assessed the relationship between leg ulcer and SCD identified from online databases.

DATA SYNTHESIS

The authors have summarized updated information on pathophysiology (vasculopathy linked to chronic hemolysis and endothelial dysfunction), diagnosis, and available treatment options to unravel the dermohematologic connection between leg ulcers and SCD.

CONCLUSIONS

It is the authors' hope that this detailed discussion of the information available on leg ulcers and SCD will lead to a better appreciation of this clinical problem by the clinicians and researchers and in turn have a long-term positive effect on the quality of life of patients with SCD. Researchers should design new trials considering these insights and potential therapeutic approaches based on current knowledge.

Antioxidant Therapy in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are a group of chronic, incurable diseases of the digestive tract, the etiology of which remains unclear to this day. IBD result in significant repercussions on the quality of patients’ life. There is a continuous increase in the incidence and prevalence of IBD worldwide, and it is becoming a significant public health burden. Pharmaceuticals commonly used in IBD management, for example, mesalamine, sulfasalazine, corticosteroids, and others, expose patients to diverse, potentially detrimental side effects and frequently do not provide sufficient disease control. The chronic inflammation underlies the etiology of IBD and closely associates with oxidative/nitrosative stress and a vast generation of reactive oxygen/nitrogen species. Relative to this, several substances with antioxidant and anti-inflammatory properties are now intensively researched as possible adjunctive or independent treatment options in IBD. Representatives of several different groups, including natural and chemical compounds will be characterized in this dissertation.

Comparison of the efficacy of multiple antioxidant and hyperbaric oxygen treatments in the prevention of ischemia and necrosis of local random McFarlane skin flap

OBJECTIVE

The aim of this study was to compare the efficacy of multiple antioxidant (Proxeed Plus (PP) with Carnitine, Selenium, Zinc, Coenzyme Q10, Vitamin C, Folic Acid, Vitamin B12) on local random skin flap healing with the hyperbaric oxygen (HBO) therapy.

METHODS

Fourty rats were equally divided into five groups (Control, PP, HBO, HBO + PP, PP + HBO + PP). Local random McFarlane skin flap was applied to all rats. Following the applications, evaluations were made biochemical (TAS, TOS, OSI, IL-1β, IL-6, TNF-α, TGF-β, VEGF) and histopathological parameters.

RESULTS

Necrosis percentage was found to be lower in the PP + HBO + PP group than all other groups whereas the necrosis percentages of PP and HBO groups were similar. Oxidative stress rates were significantly higher in the control group compared to the other groups whereas it was lower in the PP + HBO + PP group than all other groups. The inflammation parameters were the highest in the control group and the lowest in the PP + HBO + PP group. Growth factors were higher in the PP + HBO + PP group than all other groups. Epithelialization and wound healing were better in the HBO and PP groups than in the control group. The greatest healing, epithelialization and vascularization was seen in the PP + HBO + PP group. The histopathological findings in the PP + HBO + PP group were better in each inner region than in the other groups.

CONCLUSION

Biochemical and histopathological parameters have shown that PP reduces ischemia and necrosis and increases oxygenation in flap healing by providing significant improvement thanks to the multiple molecular structures in its content.

Effects of oxidative stress and apoptosis on vascularity and viability of perforator flaps

We investigated lateral thoracic and posterior thigh perforator flaps for viability, vascularization, perfusion and apoptosis in a rat model. Wistar albino rats were divided into six groups: lateral thoracic artery perforator flap (LTPF) sham, 3 × 2 cm² LTPF, 3 × 6 cm² LTPF, posterior thigh perforator flap (PTPF) sham, 3 × 2 cm² PTPF, and 3 × 6 cm² PTPF. Flap viability was determined on postoperative days 1 and 7. On day 7, flaps were photographed and their viability was measured using two-dimensional planimeter paper. Tissue samples were harvested for examination by histology and immunohistochemistry. Viability differences were statistically significant. Epithelial thickness, vascularity and number of fibroblasts were reduced in the 3 × 6 cm² groups. Neovascularization and apoptosis based on molecular tests were not significantly different among groups. Flap size and location are important factors for closure of surgical or traumatic defects. We suggest that for clinical application, wound complications will occur less frequently with perforators that nourish large areas of flaps.

Microcirculatory Disorders and Protective Role of Xuebijing in Severe Heat Stroke

This study was conducted to explore underlying mechanism of microcirculation dysfunction and protectiverole of Xuebijing in heat stroke. Forty rats were divided into: control, vehicle + heat stress (HS), superoxide dismutase (SOD) + HS, and Xuebijing + HS groups. Rats in heat stress groups were subjected to continuous heat stress in infant incubator 1 h after tail vein injection of the tested compound and spinotrapezius preparation. Velocity of blood flow through micro-vessels and vascular diameter were detected in real time. Another 27 rats were divided into: vehicle, SOD, and Xuebijing groups, then further divided into three subgroups each: control, Tcore = 38 °C, Tcore = 41 °C. Rats were sacrificed, and spinotrapezius single-cell suspensions were prepared for detecting SOD and reactive oxygen species (ROS). The results showed that heat stress decreased SOD activity, increased ROS levels, and reduced the blood flow rate. Xuebijing increased SOD activity, decreased ROS levels and exhibited a protective effect in terms of blood flow rate but was less protective than SOD. The survival time in Xuebijing + HS group was longer than that in vehicle group but shorter than that in SOD + HS group. The results suggested Xuebijing could decrease ROS levels and have protective effects in severe heat stroke.

Effects of exposure to water disinfection by-products in a swimming pool: A metabolome-wide association study

BACKGROUND

Exposure to disinfection by-products (DBPs) in drinking water and chlorinated swimming pools are associated with adverse health outcomes, but biological mechanisms remain poorly understood.

OBJECTIVES

Evaluate short-term changes in metabolic profiles in response to DBP exposure while swimming in a chlorinated pool.

MATERIALS AND METHODS

The PISCINA-II study (EXPOsOMICS project) includes 60 volunteers swimming 40min in an indoor pool. Levels of most common DBPs were measured in water and in exhaled breath before and after swimming. Blood samples, collected before and 2h after swimming, were used for metabolic profiling by liquid-chromatography coupled to high-resolution mass-spectrometry. Metabolome-wide association between DBP exposures and each metabolic feature was evaluated using multivariate normal (MVN) models. Sensitivity analyses and compound annotation were conducted.

RESULTS

Exposure levels of all DBPs in exhaled breath were higher after the experiment. A total of 6,471 metabolic features were detected and 293 features were associated with at least one DBP in exhaled breath following Bonferroni correction. A total of 333 metabolic features were associated to at least one DBP measured in water or urine. Uptake of DBPs and physical activity were strongly correlated and mutual adjustment reduced the number of statistically significant associations. From the 293 features, 20 could be identified corresponding to 13 metabolites including compounds in the tryptophan metabolism pathway.

CONCLUSION

Our study identified numerous molecular changes following a swim in a chlorinated pool. While we could not explicitly evaluate which experiment-related factors induced these associations, molecular characterization highlighted metabolic features associated with exposure changes during swimming.

Acarbose Accelerates Wound Healing via Akt/eNOS Signaling in db/db Mice

Refractory wound is a dreaded complication of diabetes and is highly correlated with EPC dysfunction caused by hyperglycemia. Acarbose is a widely used oral glucose-lowering drug exclusively for T2DM. Previous studies have suggested the beneficial effect of acarbose on improving endothelial dysfunction in patients with T2DM. However, no data have been reported on the beneficial efficacy of acarbose in wound healing impairment caused by diabetes. We herein investigated whether acarbose could improve wound healing in T2DM db/db mice and the possible mechanisms involved. Acarbose hastened wound healing and enhanced angiogenesis, accompanied by increased circulating EPC number in db/db mice. In vitro, a reversed BM-EPC dysfunction was observed after the administration of acarbose in db/db mice, as reflected by tube formation assay. In addition, a significantly increased NO production was also witnessed in BM-EPCs from acarbose treated db/db mice, with decreased O₂ levels. Akt inhibitor could abolish the beneficial effect of acarbose on high glucose induced EPC dysfunction in vitro, accompanied by reduced eNOS activation. Acarbose displayed potential effect in promoting wound healing and improving angiogenesis in T2DM mice, which was possibly related to the Akt/eNOS signaling pathway.

Evaluation of Not-Activated and Activated PRP in Hair Loss Treatment: Role of Growth Factor and Cytokine Concentrations Obtained by Different Collection Systems

Platelet rich plasma (PRP) was tested as a potential therapy for androgenetic alopecia (AGA) through two different clinical protocols in which one population (18 participants) received half-head treatment with autologous non-activated PRP (A-PRP) produced by CPunT Preparation System (Biomed Device, Modena, Italy) and the other half-head with placebo, and a second separated population in which all participants (n = 6, 3 participants per group) received treatment with calcium-activated PRP (AA-PRP) produced from one of two different PRP collection devices (Regen Blood Cell Therapy or Arthrex Angel System). For the A-PRP study, three treatments were administered over 30-day intervals. Trichoscan analysis of patients, three months post-treatment, showed a clinical improvement in the number of hairs in the target area (36 ± 3 hairs) and in total hair density (65 ± 5 hair cm²), whereas negligible improvements in hair count (1.1 ± 1.4 hairs) and density (1.9 ± 10.2 hair cm²) were seen in the region of the scalp that received placebo. Microscopic evaluation conducted two weeks after treatment showed also an increase in epidermal thickness, Ki67⁺ keratinocytes, and in the number of follicles. The AA-PRP treatment groups received a singular set of injections, and six months after the treatments were administered, notable differences in clinical outcomes were obtained from the two PRP collection devices (+90 ± 6 hair cm² versus −73 ± 30 hair cm² hair densities, Regen versus Arthrex). Growth factor concentrations in AA-PRP prepared from the two collection devices did not differ significantly upon calcium activation.

Topical application of nitrosonifedipine, a novel radical scavenger, ameliorates ischemic skin flap necrosis in a mouse model

Ischemic skin flap necrosis can occur in random pattern flaps. An excess amount of reactive oxygen species is generated and causes necrosis in the ischemic tissue. Nitrosonifedipine (NO-NIF) has been demonstrated to possess potent radical scavenging ability. However, there has been no study on the effects of NO-NIF on ischemic skin flap necrosis. Therefore, they evaluated the potential of NO-NIF in ameliorating ischemic skin flap necrosis in a mouse model. A random pattern skin flap (1.0 × 3.0 cm) was elevated on the dorsum of C57BL/6 mice. NO-NIF was administered by topical injection immediately after surgery and every 24 hours thereafter. Flap survival was evaluated on postoperative day 7. Tissue samples from the skin flaps were harvested on postoperative days 1 and 3 to analyze oxidative stress, apoptosis and endothelial dysfunction. The viable area of the flap in the NO-NIF group was significantly increased (78.30 ± 7.041%) compared with that of the control group (47.77 ± 6.549%, p < 0.01). NO-NIF reduced oxidative stress, apoptosis and endothelial dysfunction, which were evidenced by the decrease of malondialdehyde, p22phox protein expression, number of apoptotic cells, phosphorylated p38 MAPK protein expression, and vascular cell adhesion molecule-1 protein expression while endothelial nitric oxide synthase protein expression was increased. In conclusion, they demonstrated that NO-NIF ameliorated ischemic skin flap necrosis by reducing oxidative stress, apoptosis, and endothelial dysfunction. NO-NIF is considered to be a candidate for the treatment of ischemic flap necrosis.

Effect of Topical Administration of Fractions and Isolated Molecules from Plant Extracts on Skin Wound Healing: A Systematic Review of Murine Experimental Models

Background and Purpose. Skin wound healing is a dynamic process driven by molecular events responsible for the morphofunctional repair of the injured tissue. In a systematic review, we analyzed the relevance of plant fractions and isolates on skin wound healing. By revising preclinical investigations with murine models, we investigated if the current evidence could support clinical trials. Methods. Studies were selected in the MEDLINE/PubMed and Scopus databases according to the PRISMA statement. All 32 identified studies were submitted to data extraction and the methodological bias was investigated according to ARRIVE strategy. Results. The studies demonstrated that plant fractions and isolates are able to modulate the inflammatory process during skin wound healing, being also effective in attenuating the oxidative tissue damage in the scar tissue and stimulating cell proliferation, neoangiogenesis, collagen synthesis, granulation tissue expansion, reepithelialization, and the wound closure rate. However, we identified serious methodological flaws in all studies, such as the high level of reporting bias and absence of standardized experimental designs, analytical methods, and outcome measures. Conclusion. Considering these limitations, the current evidence generated from flawed methodological animal studies makes it difficult to determine the relevance of herbal medicines to treat skin wounds and derails conducting clinical studies.

Metabolomics analysis for hydroxy-L-proline-induced calcium oxalate nephrolithiasis in rats based on ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry

About 80% of kidney stones are composed of calcium oxalate (CaOx) with variable amounts of calcium phosphate, and hyperoxaluria is considered as an important factor of CaOx nephrolithiasis. However, the underlying metabolic mechanisms of CaOx nephrolithiasis remain undefined. In this study, we successfully developed a rat model with hydroxy-L-proline (HLP) -induced CaOx nephrolithiasis. Rats were continuously orally administrated with HLP for 28 days. Urine and blood samples were collected from the rats treated with or without HLP at four different time points. UPLC-Q-TOF/MS was applied to profile the abundances of metabolites. To obtain more comprehensive analysis of metabolic profiling spectrum, combination of RP-LC and HILIC were applied. We identify 42 significant differential metabolites in the urine, and 13 significant differential metabolites in the blood. Pathway analysis revealed that the pathways involved in amino acid metabolism, taurine metabolism, bile acid synthesis, energy metabolism, TCA cycle, purine metabolism, vitamin metabolism, nicotinic acid and nicotinamide metabolism have been modulated by HLP treatment. This study suggested that a number of metabolic pathways are dysfunctional in the HLP induced crystal kidney injury, and further studies on those pathways are warranted to better understand the metabolic mechanism of CaOx nephrolithiasis.