Effect of hCMSCs and liraglutide combination in ALI through cAMP/PKAc/β-catenin signaling pathway

Dulaglutide provides protection against sepsis-induced lung injury in mice by inhibiting inflammation and apoptosis

Sepsis is a dangerous condition with a high mortality rate. In addition to promoting insulin secretion in a glucose-dependent manner, glucagon-like peptide-1 (GLP-1) also exhibits anti-inflammatory properties. Dulaglutide is a glucagon-like peptide-1 receptor agonist (GLP-1 RA). In this study, we investigated the effects and mechanism of action of dulaglutide (Dul) in lipopolysaccharide (LPS) induced lung injury in mice with sepsis. In mice with LPS (15 mg/kg, ip, qd)-induced acute lung injury, the administration of dulaglutide (0.6 mg/kg, ip, qd) improved weight loss, reduced lung injury, reversed the increase in IL-1β, TNF-α, IL-6, CXCL1, CCL2 and CXCL2 expression in the lung, and reduced the infiltration of neutrophils and macrophages in the lung tissues. The decline in caspase-3, cleaved caspase-3, caspase-8, and Bcl-2/Bax expression and the increase in the number of TUNEL positive cells in the lung were reversed, suggesting that GLP-1RA could play a protective role in the lung by inhibiting inflammation and apoptosis. In addition, GLP-1RA could reduce the expression of P-STAT3 and NLRP3, suggesting that P-STAT3 and NLRP3 may be potential targets against lung injury in sepsis. Collectively, our data demonstrated that GLP-1RA exerts a protective effect against sepsis-induced lung injury through mechanisms related to the inhibition of inflammation, apoptosis, and STAT3 signaling.

Overexpression of FoxM1 optimizes the therapeutic effect of bone marrow mesenchymal stem cells on acute respiratory distress syndrome

BACKGROUND

Injury of alveolar epithelial cells and capillary endothelial cells is crucial in the pathogenesis of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Mesenchymal stem cells (MSCs) are a promising cell source for ALI/ARDS treatment. Overexpression of Fork head box protein M1 (FoxM1) facilitates MSC differentiation into alveolar type II (AT II) cells in vitro. Moreover, FoxM1 has been shown to repair the endothelial barrier. Therefore, this study explored whether overexpression of FoxM1 promotes the therapeutic effect of bone marrow-derived MSCs (BMSCs) on ARDS by differentiation of BMSCs into AT II cells or a paracrine mechanism.

METHODS

A septic ALI model was established in mice by intraperitoneal administration of lipopolysaccharide. The protective effect of BMSCs-FoxM1 on ALI was explored by detecting pathological variations in the lung, total protein concentration in bronchoalveolar lavage fluid (BALF), wet/dry (W/D) lung weight ratio, oxidative stress levels, cytokine levels, and retention of BMSCs in the lung. In addition, we assessed whether FoxM1 overexpression promoted the therapeutic effect of BMSCs on ALI/ARDS by differentiating into AT II cells using SPC-/- mice. Furthermore, the protective effect of BMSCs-FoxM1 on lipopolysaccharide-induced endothelial cell (EC) injury was explored by detecting EC proliferation, apoptosis, scratch wounds, tube formation, permeability, and oxidative stress, and analyzing whether the Wnt/β-catenin pathway contributes to the regulatory mechanism in vitro using a pathway inhibitor.

RESULTS

Compared with BMSCs-Vector, treatment with BMSCs-FoxM1 significantly decreased the W/D lung weight ratio, total BALF protein level, lung injury score, oxidative stress, and cytokine levels. With the detected track of BMSCs-FoxM1, we observed a low residency rate and short duration of residency in the lung. Notably, SPC was not expressed in SPC-/- mice injected with BMSCs-FoxM1. Furthermore, BMSCs-FoxM1 enhanced EC proliferation, migration, and tube formation; inhibited EC apoptosis and inflammation; and maintained vascular integrity through activation of the Wnt/β-catenin pathway, which was partially reversed by XAV-939.

CONCLUSION

Overexpression of FoxM1 enhanced the therapeutic effect of BMSCs on ARDS, possibly through a paracrine mechanism rather than by promoting BMSC differentiation into AT II cells in vivo, and prevented LPS-induced EC barrier disruption partially through activating the Wnt/β-catenin signaling pathway in vitro.

Association of Glucose-Lowering Drugs With Outcomes in Patients With Diabetes Before Hospitalization for COVID-19: A Systematic Review and Network Meta-analysis

IMPORTANCE

Patients with COVID-19 have a high prevalence of diabetes, and diabetes and blood glucose control are determinants of intensive care unit admission and mortality.

OBJECTIVE

To evaluate the association between COVID-19-related adverse outcomes and 8 antihyperglycemic drugs in patients with diabetes who were subsequently diagnosed and hospitalized with COVID-19.

DATA SOURCES

Data were retrieved and collected in PubMed, Embase, Cochrane Central Register, Web of Science, and ClinicalTrials.gov from database inception to September 5, 2022.

STUDY SELECTION

For this systematic review and network meta-analysis, randomized clinical trials and observational studies conducted among patients with diabetes while receiving glucose-lowering therapies for at least 14 days before the confirmation of COVID-19 infection were included after blinded review by 2 independent reviewers and consultations of disagreement by a third independent reviewer. Of 1802 studies initially identified, 31 observational studies met the criteria for further analysis.

DATA EXTRACTION AND SYNTHESIS

This study follows the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. Bayesian network meta-analyses were performed with random effects.

MAIN OUTCOMES AND MEASURES

A composite adverse outcome, including the need for intensive care unit admission, invasive and noninvasive mechanical ventilation, or in-hospital death.

RESULTS

Thirty-one distinct observational studies (3 689 010 patients with diabetes hospitalized for COVID-19) were included. The sodium-glucose cotransporter-2 inhibitors (SGLT-2is) were associated with relatively lower risks of adverse outcomes compared with insulin (log of odds ratio [logOR], 0.91; 95% credible interval [CrI], 0.57-1.26), dipeptidyl peptidase-4 inhibitors (logOR, 0.61; 95% CrI, 0.28-0.93), secretagogues (logOR, 0.37; 95% CrI, 0.02-0.72), and glucosidase inhibitors (logOR, 0.50; 95% CrI, 0.00-1.01). Based on the surface under the cumulative ranking curves value, SGLT-2is were associated with the lowest probability for adverse outcomes (6%), followed by glucagon-like peptide-1 receptor agonists (25%) and metformin (28%). A sensitivity analysis revealed that the study was reliable.

CONCLUSIONS AND RELEVANCE

These findings suggest that the use of an SGLT-2i before COVID-19 infection is associated with lower COVID-19-related adverse outcomes. In addition to SGLT-2is, glucagon-like peptide-1 receptor agonists and metformin were also associated with relatively low risk of adverse outcomes.

Study of mesenchymal stem cells derived from lung-resident, bone marrow and chorion for treatment of LPS-induced acute lung injury

BACKGROUND

Mesenchymal stem cells (MSCs) have been shown to improve acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). However, the optimal source of MSCs for cell-based therapy remains unknown. To determine which kind of MSCs are more effective, we compared the effects of rat lung resident MSC (LRMSC), human chorion-derived MSC (HMSC-C) and human bone marrow derived MSC (HMSC-BM) in LPS-induced ALI in mice.

METHODS

LPS (Pseudomonas aeruginosa) was used to induce ALI model. All three kinds of MSCs were administered via tail vein 4 h after LPS instillation. The mice were sacrificed 48 h after LPS instillation. H&E staining of lung section, wet-to-dry weight ratio of lung tissue, ratio of regulatory T cells (Tregs) and Th17 cells, and total protein concentration, leukocytes counting and cytokines in bronchoalveolar lavage fluid (BALF) were evaluated.

RESULTS

The data showed that compared with LRMSC and HMSC-BM, HMSC-C more significantly attenuated lung injury, upregulated the Tregs/Th17 cells ratio, and inhibited release of inflammatory cytokines (IL-1β, IL-6 and TNF-α) and recruitment of neutrophils and macrophages into alveolus.

CONCLUSIONS

Although all three kinds of LRMSC, HMSC-C and HMSC-BM are protective against LPS-induced lung injury, HMSC-C was more effective than LRMSC and HMSC-BM to treat LPS-induced lung injury.

The anti-inflammatory feature of glucagon-like peptide-1 and its based diabetes drugs—Therapeutic potential exploration in lung injury

Since 2005, GLP-1 receptor (GLP-1R) agonists (GLP-1RAs) have been developed as therapeutic agents for type 2 diabetes (T2D). GLP-1R is not only expressed in pancreatic islets but also other organs, especially the lung. However, controversy on extra-pancreatic GLP-1R expression still needs to be further resolved, utilizing different tools including the use of more reliable GLP-1R antibodies in immune-staining and co-immune-staining. Extra-pancreatic expression of GLP-1R has triggered extensive investigations on extra-pancreatic functions of GLP-1RAs, aiming to repurpose them into therapeutic agents for other disorders. Extensive studies have demonstrated promising anti-inflammatory features of GLP-1RAs. Whether those features are directly mediated by GLP-1R expressed in immune cells also remains controversial. Following a brief review on GLP-1 as an incretin hormone and the development of GLP-1RAs as therapeutic agents for T2D, we have summarized our current understanding of the anti-inflammatory features of GLP-1RAs and commented on the controversy on extra-pancreatic GLP-1R expression. The main part of this review is a literature discussion on GLP-1RA utilization in animal models with chronic airway diseases and acute lung injuries, including studies on the combined use of mesenchymal stem cell (MSC) based therapy. This is followed by a brief summary.

Silver Nanoparticles as Chlorhexidine and Metronidazole Drug Delivery Platforms: Their Potential Use in Treating Periodontitis

Purpose

Materials and Methods

Results

Conclusion

The Impact of Deranged Glucose Metabolism and Diabetes in the Pathogenesis and Prognosis of the Novel SARS-CoV-2: A Systematic Review of Literature

BACKGROUND

The novel coronavirus disease (COVID-19), declared a global pandemic by the World Health Organization (WHO) on March 11, 2020, and has constituted one of the most serious health challenges of the century, globally. The causative organism was initially named the 2019 novel coronavirus (2019 n CoV) but has subsequently been renamed Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The pandemic has so far infected several millions and killed about a million people worldwide. Diabetes mellitus (DM) is one of the leading causes of morbidity worldwide.

OBJECTIVES

To examine the critical role diabetes plays in the pathogenesis and prognosis of COVID-19 and to assess the emerging therapies available to fight the pandemic.

METHODS

Authors conducted a systematic review of the literature to examine the role of diabetes as comorbidity in the pathogenesis and prognosis of COVID-19 by searching PubMed and Science Direct databases mainly for articles published since the outbreak of the pandemic.

RESULTS

Both experimental and observational data from early 2020 suggested that most people with COVID-19 have comorbidities, the most dominant of which are diabetes, cardiovascular disease, and hypertension. Empirical evidence indicates that diabetic patients infected with the COVID-19 disease had the worst outcomes concerning morbidity and mortality.

CONCLUSION

A combination of underlying chronic conditions such as hypertension, obesity, and cardiovascular diseases together with altered ACE receptor expression, immune dysregulation via cytokine storm, alveolar and endothelial dysfunction, increased systemic coagulation may put individuals with diabetes at risk for COVID-19 severity. More studies are needed to elucidate how glucose- lowering drugs may modulate the host immune response in diabetic individuals, especially following the administration of potential COVID-19 vaccines.

Targeting Ferroptosis for Lung Diseases: Exploring Novel Strategies in Ferroptosis-Associated Mechanisms

Ferroptosis is an iron-dependent regulated necrosis characterized by the peroxidation damage of lipid molecular containing unsaturated fatty acid long chain on the cell membrane or organelle membrane after cellular deactivation restitution system, resulting in the cell membrane rupture. Ferroptosis is biochemically and morphologically distinct and disparate from other forms of regulated cell death. Recently, mounting studies have investigated the mechanism of ferroptosis, and numerous proteins play vital roles in regulating ferroptosis. With detailed studies, emerging evidence indicates that ferroptosis is found in multiple lung diseases, demonstrating that ferroptosis appears to be particularly important for lung diseases. The mounting interest in ferroptosis drugs specifically targeting the ferroptosis mechanism holds substantial therapeutic promise in lung diseases. The present review emphatically summarizes the functions and integrated molecular mechanisms of ferroptosis in various lung diseases, proposing that multiangle regulation of ferroptosis might be a promising strategy for the clinical treatment of lung diseases.

Anti-Diabetic Drugs GLP-1 Agonists and DPP-4 Inhibitors may Represent Potential Therapeutic Approaches for COVID-19

The fast spread of coronavirus 2019 (COVID-19) calls for immediate action to counter the associated significant loss of human life and deep economic impact. Certain patient populations like those with obesity and diabetes are at higher risk for acquiring severe COVID-19 disease and have a higher risk of COVID-19 associated mortality. In the absence of an effective and safe vaccine, the only immediate promising approach is to repurpose an existing approved drug. Several drugs have been proposed and tested as adjunctive therapy for COVID-19. Among these drugs are the glucagon-like peptide-1 (GLP-1) 2 agonists and the dipeptidylpeptidase-4 (DPP-4) inhibitors. Beyond their glucose-lowering effects, these drugs have several pleiotropic protective properties, which include cardioprotective effects, anti-inflammatory and immunomodulatory activities, antifibrotic effects, antithrombotic effects, and vascular endothelial protective properties. This narrative review discusses these protective properties and addresses their scientific plausibility for their potential use as adjunctive therapy for COVID-19 disease.

Heat shock preconditioning mesenchymal stem cells attenuate acute lung injury via reducing NLRP3 inflammasome activation in macrophages

OBJECTIVES

Acute lung injury (ALI) remains a common cause of morbidity and mortality worldwide, and to date, there is no effective treatment for ALI. Previous studies have revealed that topical administration of mesenchymal stem cells (MSCs) can attenuate the pathological changes in experimental acute lung injury. Heat shock (HS) pretreatment has been identified as a method to enhance the survival and function of cells. The present study aimed to assess whether HS-pretreated MSCs could enhance immunomodulation and recovery from ALI.

MATERIALS AND METHODS

HS pretreatment was performed at 42 °C for 1 h, and changes in biological characteristics and secretion functions were detected. In an in vivo mouse model of ALI, we intranasally administered pretreated umbilical cord-derived MSCs (UC-MSCs), confirmed their therapeutic effects, and detected the phenotypes of the macrophages in bronchoalveolar lavage fluid (BALF). To elucidate the underlying mechanisms, we cocultured pretreated UC-MSCs with macrophages in vitro, and the expression levels of inflammasome-related proteins in the macrophages were assessed.

RESULTS

The data showed that UC-MSCs did not exhibit significant changes in viability or biological characteristics after HS pretreatment. The administration of HS-pretreated UC-MSCs to the ALI model improved the pathological changes and lung damage-related indexes, reduced the proinflammatory cytokine levels, and modulated the M1/M2 macrophage balance. Mechanistically, both the in vivo and in vitro studies demonstrated that HS pretreatment enhanced the protein level of HSP70 in UC-MSCs, which negatively modulated NLR family pyrin domain containing 3 (NLRP3) inflammasome activation in alveolar macrophages. These effects were partially reversed by knocking down HSP70 expression.

CONCLUSION

HS pretreatment can enhance the beneficial effects of UC-MSCs in inhibiting NLRP3 inflammasome activation in macrophages during ALI. The mechanism may be related to the upregulated expression of HSP70.

Prescription of glucose-lowering therapies and risk of COVID-19 mortality in people with type 2 diabetes: a nationwide observational study in England

BACKGROUND

In patients with type 2 diabetes, hyperglycaemia is an independent risk factor for COVID-19-related mortality. Associations between pre-infection prescription for glucose-lowering drugs and COVID-19-related mortality in people with type 2 diabetes have been postulated but only investigated in small studies and limited to a few agents. We investigated whether there are associations between prescription of different classes of glucose-lowering drugs and risk of COVID-19-related mortality in people with type 2 diabetes.

METHODS

This was a nationwide observational cohort study done with data from the National Diabetes Audit for people with type 2 diabetes and registered with a general practice in England since 2003. Cox regression was used to estimate the hazard ratio (HR) of COVID-19-related mortality in people prescribed each class of glucose-lowering drug, with covariate adjustment with a propensity score to address confounding by demographic, socioeconomic, and clinical factors.

FINDINGS

Among the 2 851 465 people with type 2 diabetes included in our analyses, 13 479 (0·5%) COVID-19-related deaths occurred during the study period (Feb 16 to Aug 31, 2020), corresponding to a rate of 8·9 per 1000 person-years (95% CI 8·7-9·0). The adjusted HR associated with recorded versus no recorded prescription was 0·77 (95% CI 0·73-0·81) for metformin and 1·42 (1·35-1·49) for insulin. Adjusted HRs for prescription of other individual classes of glucose-lowering treatment were as follows: 0·75 (0·48-1·17) for meglitinides, 0·82 (0·74-0·91) for SGLT2 inhibitors, 0·94 (0·82-1·07) for thiazolidinediones, 0·94 (0·89-0·99) for sulfonylureas, 0·94 (0·83-1·07) for GLP-1 receptor agonists, 1·07 (1·01-1·13) for DPP-4 inhibitors, and 1·26 (0·76-2·09) for α-glucosidase inhibitors.

INTERPRETATION

Our results provide evidence of associations between prescription of some glucose-lowering drugs and COVID-19-related mortality, although the differences in risk are small and these findings are likely to be due to confounding by indication, in view of the use of different drug classes at different stages of type 2 diabetes disease progression. In the context of the COVID-19 pandemic, there is no clear indication to change prescribing of glucose-lowering drugs in people with type 2 diabetes.

FUNDING

None.

Effects of different concentrations of mesenchymal stem cells treatment on LPS-induced acute respiratory distress syndrome rat model

PURPOSE

This study was prospectively designed to investigate the effects of different concentrations of mesenchymal stem cells treatment on respiratory mechanics, oxygenation, hemodynamics and inflammatory response in LPS-induced acute respiratory distress syndrome (ARDS) rat model. Methods: One hundred and twenty six LPS-induced ARDS model rats (weighted 200-220 g) were randomly divided into three groups: 1) Control group (N = 42); 2) low-dose hUC-MSC treatment group (MSC group 1, 1x107 cell/kg, N = 42); 3) high-dose hUC-MSC treatment group (MSC group 2, 2x107 cell/kg, N = 42), sham operation group as healthy group (N = 15). The rats were observed closely for 24 hours after hUC-MSC treatment, and the survival rate was calculated. At 24 hours, all rats were tested for hemodynamics, blood gas analysis, heart, lung, liver and kidney functions, inflammatory factors detection in blood samples and broncho-alveolar lavage fluid (BALF). The lung tissue of the rats was collected for HE staining analysis. Results: After LPS injection, ARDS was obvious in all LPS-infused rat groups, consistent with severe acute lung injury and high death rate. However, compared with the control group, a single intravenous injection hUC-MSC at dose of 1 × 107 cells/kg (low dose group) and 2 × 107 cells/kg (high dose group) reduced the mortality of rats with LPS-induced ARDS, as well as improving the lung function, increased the arterial oxygen pressure, improved the heart function, and reduced the levels of inflammatory factors including IL-1β, IL-6, and TNF-α. In addition, the high dose MSC group showed better lung injury therapeutic effects than the low dose MSC group. Data from this study demonstrated that injection of hUC-MSC had a significant therapeutic effect in treating the rat model of LPS-induced ARDS and multiple organ function injury.

The role and mechanism of β-arrestin2 in signal transduction

β-arrestin2 is a ubiquitously expressed scaffold protein localized on the cytoplasm and plasma membrane. It was originally found to bind to GPCRs, uncoupling G proteins and receptors' binding and inhibiting the signal transduction of the GPCRs. Further investigations have revealed that β-arrestin2 not only mediates the desensitization of GPCRs but also serves as a multifunctional scaffold to mediate receptor internalization, kinase activation, and regulation of various signaling pathways, such as TLR4/NF-κB, MAPK, Wnt, TGF-β, and AMPK/mTOR pathways. β-arrestin2 regulates cell invasion, migration, autophagy, angiogenesis, and anti-inflammatory effects by regulating various signaling pathways, which play a vital role in many physiological and pathological processes. This paper reviews the structure and function of β-arrestin2, the regulation of β-arrestin2 based signaling pathways. The role and mechanism of β-arrestin2 signaling have been delineated in sufficient detail. The prospect of regulating the expression and activity of β-arrestin2 in multisystem diseases holds substantial therapeutic promise.

Aldosterone alleviates lipopolysaccharide-induced acute lung injury by regulating epithelial sodium channel through PI3K/Akt/SGK1 signaling pathway

Reduced alveolar fluid clearance (AFC) is a major pathological feature of acute lung injury (ALI). Epithelial sodium channel (ENaC) plays a key role in regulating the transport of Na⁺ and clearing alveolar edema fluid effectively. ENaC has been reported to be regulated by aldosterone in the distal collecting tube of the kidney. We hypothesized whether aldosterone regulated ENaC in alveolar epithelium and correspondingly played a role in ALI. In this study we found that the expression of aldosterone synthesis encoding gene, CYP11B2, and ENaC were decreased in the lung tissue of LPS-induced ALI mice. Furthermore, aldosterone alleviated ALI by increasing the expression of ENaC-α and relieving pulmonary edema. Besides, we found that aldosterone upregulated ENaC-α through PI3K/Akt/SGK1 pathway. In conclusion, our study demonstrated that aldosterone attenuated pulmonary edema by upregulating ENaC-α through the PI3K/Akt/SGK1 pathway in LPS-induced ALI, indicating that aldosterone might be a promising adjuvant drug for ALI treatment.

Metabolic Syndrome “Interacts” With COVID-19

COVID-19, caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has emerged as a global pandemic and poses a great threat to public health and society in general. SARS-CoV-2 invades cells via its spike protein, which initiates endocytosis via its binding to host receptor angiotensin-converting enzyme 2 (ACE2) and membrane fusion after being cleaved by the serine protease, TMPRSS2. The most common clinical manifestations are fever, dry cough, fatigue and abnormalities on chest computed tomography (CT). However, some patients rapidly progress to severe pneumonia and develop acute respiratory distress syndrome (ARDS). Furthermore, SARS-CoV-2 triggers a severe cytokine storm, which may explain the deterioration of pre-existing metabolic disorders. Interestingly, conversely, underlying metabolic-related diseases, including hypertension, diabetes, cardiovascular disease, etc., are associated with progression and poor prognosis of COVID-19. The putative mechanisms are dysregulation of ACE2, impaired immunity especially uncontrolled hyperinflammation, hypercoagulability, etc. In this review, we summarize the crosstalk between COVID-19 and metabolic diseases and propose that in addition to controlling COVID-19, more intensive attention should be paid to the symptomatic treatment and prevention of pre-existing and foreseeable metabolic comorbidities.Significance statement: Coronavirus disease 2019 (COVID-19) has rapidly spread worldwide and has exerted a great influence on public health and society, urging scientists to find efficient therapeutics. Metabolic disturbance involving various organs has been found in these patients, including diabetes, fatty liver, acute kidney injury (AKI), etc. In turn, these preexisting metabolic syndromes could exacerbate COVID-19. In this review, we focus on the close interaction between COVID-19 and metabolic syndrome, as well as the potential of repurposing metabolic-related drugs and the importance of treating metabolic diseases in COVID-19 patients.

Non-insulin anti-diabetic agents in patients with type 2 diabetes and COVID-19: A Critical Appraisal of Literature

BACKGROUND & AIMS

Several observational studies have recently reported the outcomes of non-insulin anti-diabetic agents (ADA) in patients with T2DM and coronavirus disease 2019 (COVID-19). We sought to review the literature to appraise the clinicians on these outcomes.

METHODS

A literature search using the specific keywords was carried out in the database of PubMed, MedRxiv and Google Scholar up till December 11, 2020 applying Boolean method. Full text of all the relevant articles that reported the outcomes of ADA in patients with T2DM and COVID-19 were retrieved. Subsequently, an appraisal of literature report was narratively presented.

RESULTS

Available studies that reported the outcomes of ADA are either case series or retrospective cohorts or prospective observational studies, in absence of the randomized controlled trials (RCTs). Results from these observational studies suggest that amongst all the non-insulin ADA, metformin users prior to the hospitalization had improved outcomes compared to the non-users. Data for dipeptidyl-peptidase-4 inhibitors (DPP-4i) are encouraging although inconsistent. No documentation of any harm or benefit has been observed for sulfonylureas (SUs), sodium glucose co-transporter-2 inhibitors (SGLT-2i) and glucagon-like peptide receptor agonists (GLP-1RAs). No data is yet available for pioglitazone.

CONCLUSION

Metformin and DPP-4i should be continued in patients with T2DM until hospitalization or unless contraindicated. No evidence of harm suggests that SUs, SGLT-2i or GLP-1RAs may not be stopped unless very sick, hospitalized or contraindicated. The results from RCTs are needed to claim any meaningful benefit with either metformin or DPP-4i in patients with T2DM and COVID-19.

Insulinoma induces a hyperinsulinemia-mediated decrease of GLUT2 and GLP1 receptor in normal pancreatic β-cells

There have been several clinical reports of transient postoperative hyperglycemia in patients with insulinoma, but the effect of insulinoma on normal β-cells has not been investigated. We examined the glucose transporter 2 (GLUT2) and glucagon-like peptide 1 receptor (GLP1R) expression in normal pancreatic β-cells of five patients with insulinoma and five patients with normal glucose tolerance (NGT) as controls. The positive rate of GLUT2-or GLP1R-positive islets in the nontumor area was calculated by the ratio with the analyzed islets. For functional in vitro analyses, q-PCR and Western blotting were performed after insulin loading on MIN6 cells. The expression rates of both GLUT2 and GLP1R were significantly lower in nontumor area islets of insulinoma patients than in patients with NGT (GLUT2: 31.6 ± 15.3% vs 95.9 ± 6.7%, p < 0.01, GLP1R: 66.8 ± 15.0% vs 96.7 ± 5.0%, p < 0.01). Exposure of MIN6 cells to high concentrations of insulin resulted in a significant decrease in GLUT2 protein for 12 h and GLP1R protein for 24 h (GLUT2; 1.00 ± 0.079 vs 0.81 ± 0.04. p = 0.02, GLP1R; 1.00 ± 0.10 vs 0.50 ± 0.24, p = 0.03) but not in those mRNAs. Our findings show that insulinoma is associated with the downregulation of GLUT2 and GLP1R expression in nontumor area islets. These phenomena may be caused by high levels of insulin.

[Pathogenic role leukotriene B4 in lung injury induced by lung-protective mechanical ventilation in rabbits]

OBJECTIVE

To elucidate the pathogenic role of leukotriene B4 (LTB4) in pulmonary hyper-permeability and inflammation induced by lung-protective mechanical ventilation (LPMV) in rabbits.

METHODS

Thirty-two healthy Japanese white rabbits were randomized into 4 groups for treatment with vehicle or bestatin (a leukotriene A4 hydrolase inhibitor that inhibits LTB4 production) administered intragastrically at the daily dose of 8 mg/kg for 5 days, followed by sham operation (group S and group BS, respectively, in which the rabbits were anesthetized only) or LPMV (group PM and group BPM, respectively, in which the rabbits received ventilation with 50% oxygen at a tidal volume of 8 mL/kg for 5 h). The concentrations of LTB4 and cyclic adenosine monophosphate (cAMP) in the lung tissues were analyzed by ELISA. cAMP content, protein kinase A (PKA) protein expression and the Rap1-GTP protein to total Rap1 protein ratio were determined to assess the activities of cAMP/PKA and Rap1 signaling pathways. The lung injury was evaluated by assessing lung permeability index, lung wet/dry weight ratio, polymorphonuclear leukocyte (PMN) count in bronchoalveolar lavage fluid (BALF), pulmonary myeloperoxidase (MPO) activity and lung histological scores.

RESULTS

None of the examined parameters differed significantly between group S and group BS. All the parameters with the exception of lung histological score increased significantly in group PM and group BPM as compared to those in group S (P < 0.05). Compared with those in PM group, the rabbits in group BPM showed significantly reduced LTB4 production in the lungs (P < 0.05), up-regulated cAMP/ PKA and Rap1 signaling pathway activities (P < 0.05), and alleviated lung hyper-permeability and inflammation (P < 0.05).

CONCLUSIONS

LPMV can induce LTB4 overproduction to down-regulate cAMP/PKA and Rap1 signaling pathways in the lungs of rabbits, which results in lung hyper-permeability and inflammation. Bestatin can inhibit LTB4 production in the lungs to protect against LPMV-induced lung hyper-permeability and inflammation.

Antidiabetes Agents against Sars-Cov-2 Infection

People with chronic diseases represent a population at major risk of infection and complications from Sars-Cov-2 (COVID-19). Diabetes represents one of the most important comorbidities related to the severity of viral infection caused by the new Sars-Cov-2. Diabetes patients have a higher risk of serious complications caused by Sars-Cov-2 infection, such as severe acute respiratory syndrome, a hyperinflammatory state associated with multi-organ dysfunction. Given the importance of the link between COVID-19 and diabetes, it is essential to better manage glycemic normalization and infection in this category of patients to avoid serious complications. However, for some antidiabetes agents, there is evidence of efficacy against Sars-Cov-2 extra glycemic normalization. The objective of this article is to provide an overview of the potential therapeutic benefits to fight Sars-Cov-2 infection with antidiabetic agents.

Prevention and management of COVID-19 among patients with diabetes: an appraisal of the literature

The coronavirus disease 2019 (COVID-19) pandemic has emerged as one of the greatest challenges faced by humankind in the recent past. People with diabetes and related comorbidities are at increased risk of its complications and of COVID-19-related death. Older age, multi-morbidity, hyperglycaemia, cardiac injury and severe inflammatory response are predictors of poor outcome. The complex interplay between COVID-19, diabetes and the effects of related therapies is being explored. Most patients experience a mild illness with COVID-19, while people with diabetes are at increased risk of severe disease. Optimising glycaemic control and adopting measures to prevent disease spread are critical aspects. The management of mild disease is supportive, while very many immunomodulatory and antiviral therapies are being investigated for the treatment of severe disease. Several of these agents have specific considerations for use in people with diabetes. Since mass population lockdowns are considered a key step in controlling disease spread, it follows that, in addition to the direct vulnerability to severe COVID-19, people with diabetes can be affected by limited access to healthcare, insulin, other medications and blood glucose monitoring equipment. Measures to prevent disease spread at the individual and community level are the key to mitigating the rapidly escalating pandemic, while agents for chemoprophylaxis and vaccines are being explored. People with diabetes should be recognised as a vulnerable group for complicated disease and are at risk during times of disturbed social systems. Strategies are needed to safeguard the health of patients with diabetes during the pandemic. This review summarises the current knowledge and perceived challenges for prevention and management of COVID-19 in people with diabetes.

Assessment of risk, severity, mortality, glycemic control and antidiabetic agents in patients with diabetes and COVID-19: A narrative review

AIMS

Rising prevalence of non-communicable diseases world-wide has made diabetes an important comorbidity in patients with coronavirus disease-19 (COVID-19). We sought to review the risk, severity and mortality in COVID-19 and its relation to the glycemic control, and role of anti-diabetic agents in patients with diabetes.

METHODS

A Boolean search was made in PubMed, MedRxiv and Google Scholar database until May 10, 2020 and full articles with supplementary appendix were retrieved using the specific key words related to the topic.

RESULTS

There is a high prevalence of diabetes in patients with COVID-19. Patients with diabetes had a significantly more severe variety of COVID-19 and increased mortality, compared to the groups without diabetes. Moreover, poor glycemic control is associated with a significantly higher severe COVID-19 and increased mortality, compared to the well-controlled glycemic groups. No data currently available for or against any anti-diabetic agents in COVID-19.

CONCLUSIONS

Diabetes, in particular poorly-controlled group is associated with a significantly higher risk of severe COVID-19 and mortality. This calls for an optimal glycemic control and an increased emphasis on future preventative therapies including the vaccination programs for these groups in addition to the traditional risk prevention such as social distancing and self-isolation.

Mesenchymal stem cells combined with liraglutide relieve acute lung injury through apoptotic signaling restrained by PKA/β-catenin

Background

ARDS and ALI are life-threatening diseases with extremely high mortality in patients. Different sources of MSCs could mitigate the symptoms of ALI from diverse mechanisms. Liraglutide is an activator of glucagon-like peptide-1 receptor (GLP-1R) that activates anti-apoptotic pathways and exerts anti-inflammatory effects. We mainly compared the effects of human chorionic villus-derived mesenchymal stem cells (hCMSCs), human bone marrow-derived mesenchymal stem cells (hBMSCs), and human adipose-derived mesenchymal stem cells (hAMSCs) on the treatment of ALI and explored the apoptosis mechanism of combination MSCs of liraglutide.

Methods

The proliferation of MSCs was detected by MTT assay. Western blot and RT-qPCR were used to detect the expression of GLP-1R, SPC, Ang-1, and KGF in MSCs stimulated by LPS and liraglutide. By using flow cytometry and TUNEL assay to compare the apoptosis of three MSCs under the action of LPS and liraglutide, we selected hCMSCs as the target cells to study the expression of apoptotic protein through the PKA/β-catenin pathway. In ALI animal models, we observed the effects of liraglutide alone, MSCs alone, and MSCs combined with liraglutide by H&E staining, cell counting, immunohistochemistry, and ELISA assay.

Results

We demonstrated that LPS attenuates the proliferation of the three MSCs and the expression of GLP-1R. Liraglutide could reverse the effects of LPS; increase the expression of SPC, Ang-1, and KGF; and can reduce the apoptosis of three MSCs through the PKA/β-catenin pathway. In the LPS-induced ALI model, MSCs combined with liraglutide showed a significant therapeutic effect, and hCMSCs combined with liraglutide have advantages in the treatment of ALI.

Conclusions

The therapeutic effect of combination MSCs of liraglutide on ALI was higher than that of MSCs alone or liraglutide alone, and liraglutide could alleviate the symptoms of ALI by reducing MSCs apoptosis.