Beneficial effects of Red Light-Emitting Diode treatment in experimental model of acute lung injury induced by sepsis

Repercussion of inflammatory bowel disease on lung homeostasis: The role of photobiomodulation

Inflammatory bowel diseases (IBD) are chronic and multifactorial diseases characterized by dysfunction of the intestinal mucosa and impaired immune response. Data show an important relationship between intestine and respiratory tract. The treatments of IBD are limited. Photobiomodulation (PBM) is an effective anti-inflammatory therapy. Our objective was to evaluate the repercussion of IBD as well as its treatment with PBM on pulmonary homeostasis. Male Wistar rats were submitted to IBD induction by acetic acid and treated or not with PBM. Rats were irradiated with red LED on both right and left sides of the ventral surface and beside the external anal region during 3 consecutive days (wavelenght 660 nm, power 100 mw, total energy 15 J and time of irradiation 150 s per point). Our results showed that IBD altered pulmonary homeostasis, since we observed an increase in the histopathological score, in myeloperoxidase activity (MPO), in mast cell degranulation, and in the release and gene expression of cytokines. We also showed that PBM treatment reduced biomarkers of IBD and reverted all augmented parameters in the lung, restoring its homeostasis. Thus, we confirm experimentally the important gut-lung axis and the role of PBM as a promising therapy.

LED irradiation at 630 nm alleviates collagen-induced arthritis in mice by inhibition of NF-κB-mediated MMPs production

Matrix metallopreteinase (MMP), a family of matrix degrading enzyme, plays a significant role in persistent and irreversible joint damage in rheumatoid arthritis (RA). Photobiomodulatory therapy (PBMT) has become an emerging adjunct therapy for RA. However, the molecular mechanism of PBMT on RA remains unclear. The purpose of this study is to explore the effect of 630 nm light emitting diode (LED) irradiation on RA and its underly molecular mechanism. Arthritis clinic scores, histology analysis and micro-CT results show that 630 nm LED irradiation ameliorates collagen-induced arthritis (CIA) in mice with the reduction of the extents of paw swelling, inflammation and bone damage. 630 nm LED irradiation significantly reduces MMP-3 and MMP-9 levels and inhibits p65 phosphorylation level in the paws of CIA mice. Moreover, 630 nm LED irradiation significantly inhibits the mRNA and protein levels of MMP-3 and MMP-9 in TNF-α-treated MH7A cells, a human synovial cell line. Importantly, 630 nm LED irradiation reduces TNF-α-induced the phosphorylated level of p65 but not alters STAT1, STAT3, Erk1/2, JNK and p38 phosphorylation levels. Immunofluorescence result showed that 630 nm LED irradiation blocks p65 nuclear translocation in MH7A cells. In addition, other MMPs mRNA regulated by NF-κB were also significantly inhibited by LED irradiation in vivo and in vitro. These results indicates that 630 nm LED irradiation reduces the MMPs levels to ameliorate the development of RA by inhibiting the phosphorylation of p65 selectively, suggesting that 630 nm LED irradiation may be a beneficial adjunct therapy for RA.Graphical abstract.

Fecal microbiota transplantation from HUC-MSC-treated mice alleviates acute lung injury in mice through anti-inflammation and gut microbiota modulation

Introduction

Acute lung injury (ALI) is a severe respiratory tract disorder facilitated by dysregulated inflammation, oxidative stress and intestinal ecosystem. Fecal microbiota transplantation (FMT) is a rapid method for gut microbiota (GM) reconstruction. Furthermore, our previous studies have confirmed that human umbilical cord mesenchymal stromal cells (HUC-MSCs) can alleviate ALI by improving GM composition. Therefore, we aimed to explore the efficacy and mechanism of FMT from HUC-MSCs-treated mice on ALI.

Methods

In brief, fresh feces from HUC-MSCs-treated mice were collected for FMT, and the mice were randomly assigned into NC, FMT, LPS, ABX-LPS, and ABX-LPS-FMT groups (n = 12/group). Subsequently, the mice were administrated with antibiotic mixtures to deplete GM, and given lipopolysaccharide and FMT to induce ALI and rebuild GM. Next, the therapeutic effect was evaluated by bronchoalveolar lavage fluid (BALF) and histopathology. Immune cells in peripheral blood and apoptosis in lung tissues were measured. Furthermore, oxidative stress- and inflammation-related parameter levels were tested in BALF, serum, lung and ileal tissues. The expressions of apoptosis-associated, TLR4/NF-κB pathway-associated, Nrf2/HO-1 pathway related and tightly linked proteins in the lung and ileal tissues were assessed. Moreover, 16S rRNA was conducted to assess GM composition and distribution.

Results

Our results revealed that FMT obviously improved the pathological damage of lung and ileum, recovered the immune system of peripheral blood, decreased the cell apoptosis of lung, and inhibited inflammation and oxidative stress in BALF, serum, lung and ileum tissues. Moreover, FMT also elevated ZO-1, claudin-1, and occludin protein expressions, activating the Nrf2/HO-1 pathway but hindering the TLR4/NF-κB pathway. Of note, the relative abundances of Bacteroides, Christensenella, Coprococcus, and Roseburia were decreased, while the relative abundances of Xenorhabdus, Sutterella, and Acinetobacter were increased in the ABX-LPS-FMT group.

Conclusion

FMT from HUC-MSCs-treated mice may alleviate ALI by inhibiting inflammation and reconstructing GM, additionally, we also found that the TLR4/NF-κB and Nrf2/HO-1 pathways may involve in the improvement of FMT on ALI, which offers novel insights for the functions and mechanisms of FMT from HUC-MSCs-treated mice on ALI.

A Multifunctional Neutralizing Antibody-Conjugated Nanoparticle Inhibits and Inactivates SARS-CoV-2

The outbreak of 2019 coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a global pandemic. Despite intensive research, the current treatment options show limited curative efficacies. Here the authors report a strategy incorporating neutralizing antibodies conjugated to the surface of a photothermal nanoparticle (NP) to capture and inactivate SARS-CoV-2. The NP is comprised of a semiconducting polymer core and a biocompatible polyethylene glycol surface decorated with high-affinity neutralizing antibodies. The multifunctional NP efficiently captures SARS-CoV-2 pseudovirions and completely blocks viral infection to host cells in vitro through the surface neutralizing antibodies. In addition to virus capture and blocking function, the NP also possesses photothermal function to generate heat following irradiation for inactivation of virus. Importantly, the NPs described herein significantly outperform neutralizing antibodies at treating authentic SARS-CoV-2 infection in vivo. This multifunctional NP provides a flexible platform that can be readily adapted to other SARS-CoV-2 antibodies and extended to novel therapeutic proteins, thus it is expected to provide a broad range of protection against original SARS-CoV-2 and its variants.

Local (but not systemic) photobiomodulation treatment reduces mast cell degranulation, eicosanoids, and Th2 cytokines in an experimental model of allergic rhinitis

Allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa, and is a worldwide health problem with a significant impact on the quality of life. The main goal of AR treatment is to relieve symptoms. However, standard treatments have considerable side effects or are not effective. Photobiomodulation (PBM) therapy has emerged as an alternative treatment. Here, we evaluated the effects of transcutaneous systemic (tail) or local (skin over nostrils) PBM using a 660-nm light-emitting diode (LED) array. Adult rats were assigned into 4 groups: basal, as non-manipulated animals; Sham, as rats sensitized with 7 intradermal injections of ovalbumin (OVA) plus alum followed by intranasal instillation with OVA (2%) daily for 7 days; and the LPBM and SPBM groups, in which the animals were treated with PBM (local or systemic) immediately after the last instillation of OVA (1%) daily for 3 days. Our results showed that local PBM treatment reduced mast cell degranulation in the nasopharynx and nostrils; levels of leukotriene B4, thromboxane A2, and interleukin 4 (IL-4) in the nasopharynx; and gene expression of IL-4. Moreover, we showed higher levels and gene expression of IL-10 after local PBM treatment. Systemic PBM treatment did not change any of the evaluated parameters. In conclusion, our data showed that local (but not systemic) treatment with PBM could improve parameters related to AR in an animal model, and should be tested clinically.

Sunlight Exposure and Phototherapy: Perspectives for Healthy Aging in an Era of COVID-19

Most humans depend on sunlight exposure to satisfy their requirements for vitamin D₃. However, the destruction of the ozone layer in the past few decades has increased the risk of skin aging and wrinkling caused by excessive exposure to ultraviolet (UV) radiation, which may also promote the risk of skin cancer development. The promotion of public health recommendations to avoid sunlight exposure would reduce the risk of skin cancer, but it would also enhance the risk of vitamin D₃ insufficiency/deficiency, which may cause disease development and progression. In addition, the ongoing global COVID-19 pandemic may further reduce sunlight exposure due to stay-at-home policies, resulting in difficulty in active and healthy aging. In this review article, we performed a literature search in PubMed and provided an overview of basic and clinical data regarding the impact of sunlight exposure and vitamin D₃ on public health. We also discuss the potential mechanisms and clinical value of phototherapy with a full-spectrum light (notably blue, red, and near-infrared light) as an alternative to sunlight exposure, which may contribute to combating COVID-19 and promoting active and healthy aging in current aged/superaged societies.

Early cases of acute infectious respiratory syndrome treated with photobiomodulation, diagnosis and intervention: Two case reports

PBMT using 630 + 660 nm wavelengths transcutaneously at 7 cm above chest area irradiating lungs and heart regions of patients with acute, infectious respiratory syndrome alleviated their respiratory symptoms, mitigated pulmonary inflammation and hypoxia. PBMT could prevent more severe respiratory distress requiring emergency care and reduce the strain on healthcare. This case report's clinical experience can be the basis of future research evaluating oxygen saturation levels pre- and post-PBMT.

Red light-emitting diode treatment improves tissue recovery in DSS-induced colitis in mice

Inflammatory bowel diseases are debilitating illnesses characterized by severe inflammation of the gastrointestinal tract. Treatments currently available are expensive and ineffective. We here investigated the role of red-light emitting diode (LED) on dextran sodium sulfate (DSS)-induced colitis. DSS was added to the drinking water of male mice at days 0, 2, 4 and withdrawn at day 6. LED irradiation was performed daily for 90s from day 6 to 9 on the right and left sides of the ventral surface and beside the external anal region. LED treatment decreased the amount of crypt dysplasia/edema, inflammatory infiltrates and ulcers, attenuated apoptosis and increased proliferation of crypt cells. Also, LED treatment induced expression of annexin A1 in the damaged epithelium, preserved the organization of claudin-1 and skewed cytokine profiling towards a more anti-inflammatory status. Thus, LED treatment promotes structural protection and modulates the inflammatory response, constituting a potential non-invasive and low-cost combined therapy to help patients achieve disease remission.

Prenatal programming of the immune response induced by maternal periodontitis: Effects on the development of acute lung injury in rat pups

AIMS

Oral cavity pathogens play an important systemic role, modulating the development of several diseases. Periodontitis is a very common oral disease associated with dental biofilm. It is characterized by gum inflammation, periodontal ligament degeneration, dental cementum and alveolar bone loss. Studies point to the association between maternal periodontitis and adverse outcomes during pregnancy. However, they did not evaluate the impact of maternal periodontitis in the offspring. Thus, our objective was to investigate the effects of maternal periodontitis in the immune system of offspring.

MATERIAL AND METHODS

For this evaluation we induced acute lung injury in rat pups. Pregnant rats were submitted or not to periodontitis by ligature technique. Thirty days after the birth, offspring was submitted to acute lung inflammation by administration of lipopolysaccharide (LPS, Salmonella abortus equi, 5 mg/kg, ip).

KEY FINDINGS

Our results showed that maternal periodontitis increased myeloperoxidase activity, the levels of TNF-alpha and IL-17A in the bronchoalveolar fluid, the gene expression of TNF-alpha, IL-17A, and cyclooxygenases 1 and 2. In addition, maternal periodontitis did not alter the number of leukocytes migrated into the lung, tracheal responsiveness, expression of TLR4 and NF-KB translocation.

SIGNIFICANCE

This study showed prenatal programming of the immune response induced by maternal periodontitis, and reinforces the importance of oral health care during pregnancy.

Effect of systemic photobiomodulation in the course of acute lung injury in rats

Acute lung injury (ALI) is a severe, multifactorial lung pathology characterized by diffuse alveolar injury, inflammatory cell infiltration, alveolar epithelial barrier rupture, alveolar edema, and impaired pulmonary gas exchange, with a high rate of mortality; and sepsis is its most common cause. The mechanisms underlying ALI due to systemic inflammation were investigated experimentally by systemic lipopolysaccharide (LPS) administration. Photobiomodulation (PBM) has been showing good results for several inflammatory diseases, but there are not enough studies to support the real benefits of its use, especially systemically. Considering that ALI is a pathology with high morbidity and mortality, we studied the effect of systemic PBM with red light-emitting diode (LED) (wavelength 660 nm; potency 100 mW; energy density 5 J/cm; total energy 15 J; time 150 s) in the management of inflammatory parameters of this disease. For this, 54 male Wistar rats were submitted to ALI by LPS injection (IP) and treated or not with PBM systemically in the tail 2 and 6 h after LPS injection. Data were analyzed by one-way ANOVA followed by Student's Newman-Keuls. Our results point to the beneficial effects of systemic PBM on the LPS-induced ALI, as it reduced the number of neutrophils recruited into the bronchoalveolar lavage, myeloperoxidase activity, and also reduced interleukins (IL) 1β, IL-6, and IL-17 in the lung. Even considering the promising results, we highlight the importance of further studies to understand the mechanisms involved, and especially the dosimetry, so that in near future, we can apply this knowledge in clinical practice.

Obeticholic acid alleviate lipopolysaccharide-induced acute lung injury via its anti-inflammatory effects in mice

Acute lung injury (ALI) is a common disease that may result in acute respiratory failure and death. However, there are still no effective treatments for ALI. Several studies have shown that farnesoid X receptor (FXR) has an anti-inflammatory effect. We investigated the effects of obeticholic acid (OCA), an agonist of FXR, on Lipopolysaccharide (LPS)-induced ALI in mice. Sixty male mice were randomly divided into six groups, and orally administered with or without OCA once daily for 3 consecutive days before LPS (1.0 mg/kg). Animals were sacrificed at 0 h, 2 h or 6 h after LPS. As expected, OCA enhanced pulmonary FXR activity. OCA prevented LPS-induced ALI. Additional experiment showed that OCA alleviated LPS-induced up-regulation of pulmonary pro-inflammatory and chemokine genes. Moreover, OCA also repressed LPS-induced the release of TNF-α and KC in serum and bronchoalveolar lavage fluid. In contrast, OCA further up-regulated LPS-induced the expression of Il-10, an anti-inflammatory cytokine. Further study showed that OCA inhibited LPS-evoked NF-κB signaling in the lungs. OCA attenuated LPS-induced ERK1/2, JNK, p38 and Akt phosphorylation in the lungs. Overall, these results suggest that OCA prevent LPS-induced ALI may be through enhancing pulmonary FXR activity and then blockading several inflammatory signaling pathways.

Induction of a Long Noncoding RNA Transcript, NR_045064, Promotes Defense Gene Transcription and Facilitates Intestinal Epithelial Cell Responses against Cryptosporidium Infection

Cryptosporidium is an important opportunistic intestinal pathogen for immunocompromised individuals and a common cause of diarrhea in young children in developing countries. Gastrointestinal epithelial cells play a central role in activating and orchestrating host immune responses against Cryptosporidium infection, but underlying molecular mechanisms are not fully understood. We report in this paper that C. parvum infection causes significant alterations in long noncoding RNA (lncRNA) expression profiles in murine intestinal epithelial cells. Transcription of a panel of lncRNA genes, including NR_045064, in infected cells is controlled by the NF-κB signaling. Functionally, inhibition of NR_045064 induction increases parasite burden in intestinal epithelial cells. Induction of NR_045064 enhances the transcription of selected defense genes in host cells following C. parvum infection. Epigenetic histone modifications are involved in NR_045064-mediated transcription of associated defense genes in infected host cells. Moreover, the p300/MLL-associated chromatin remodeling is involved in NR_045064-mediated transcription of associated defense genes in intestinal epithelial cells following C. parvum infection. Expression of NR_045064 and associated genes is also identified in intestinal epithelium in C57BL/6J mice following phosphorothioate oligodeoxynucleotide or LPS stimulation. Our data demonstrate that lncRNAs, such as NR_045064, play a role in regulating epithelial defense against microbial infection.