The complex combination of COVID-19 and diabetes: pleiotropic changes in glucose metabolism

Novel COVID-19 biomarkers identified through multi-omics data analysis: N-acetyl-4-O-acetylneuraminic acid, N-acetyl-L-alanine, N-acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate

This study aims to apply machine learning models to identify new biomarkers associated with the early diagnosis and prognosis of SARS-CoV-2 infection.Plasma and serum samples from COVID-19 patients (mild, moderate, and severe), patients with other pneumonia (but with negative COVID-19 RT-PCR), and healthy volunteers (control) from hospitals in four different countries (China, Spain, France, and Italy) were analyzed by GC-MS, LC-MS, and NMR. Machine learning models (PCA and PLS-DA) were developed to predict the diagnosis and prognosis of COVID-19 and identify biomarkers associated with these outcomes.A total of 1410 patient samples were analyzed. The PLS-DA model presented a diagnostic and prognostic accuracy of around 95% of all analyzed data. A total of 23 biomarkers (e.g., spermidine, taurine, L-aspartic, L-glutamic, L-phenylalanine and xanthine, ornithine, and ribothimidine) have been identified as being associated with the diagnosis and prognosis of COVID-19. Additionally, we also identified for the first time five new biomarkers (N-Acetyl-4-O-acetylneuraminic acid, N-Acetyl-L-Alanine, N-Acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate) that are also associated with the severity and diagnosis of COVID-19. These five new biomarkers were elevated in severe COVID-19 patients compared to patients with mild disease or healthy volunteers.The PLS-DA model was able to predict the diagnosis and prognosis of COVID-19 around 95%. Additionally, our investigation pinpointed five novel potential biomarkers linked to the diagnosis and prognosis of COVID-19: N-Acetyl-4-O-acetylneuraminic acid, N-Acetyl-L-Alanine, N-Acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate. These biomarkers exhibited heightened levels in severe COVID-19 patients compared to those with mild COVID-19 or healthy volunteers.

SARS-CoV-2 and its Multifaceted Impact on Bone Health: Mechanisms and Clinical Evidence

PURPOSE OF REVIEW

SARS-CoV-2 infection, the culprit of the COVID-19 pandemic, has been associated with significant long-term effects on various organ systems, including bone health. This review explores the current understanding of the impacts of SARS-CoV-2 infection on bone health and its potential long-term consequences.

RECENT FINDINGS

As part of the post-acute sequelae of SARS-CoV-2 infection, bone health changes are affected by COVID-19 both directly and indirectly, with multiple potential mechanisms and risk factors involved. In vitro and preclinical studies suggest that SARS-CoV-2 may directly infect bone marrow cells, leading to alterations in bone structure and osteoclast numbers. The virus can also trigger a robust inflammatory response, often referred to as a "cytokine storm", which can stimulate osteoclast activity and contribute to bone loss. Clinical evidence suggests that SARS-CoV-2 may lead to hypocalcemia, altered bone turnover markers, and a high prevalence of vertebral fractures. Furthermore, disease severity has been correlated with a decrease in bone mineral density. Indirect effects of SARS-CoV-2 on bone health, mediated through muscle weakness, mechanical unloading, nutritional deficiencies, and corticosteroid use, also contribute to the long-term consequences. The interplay of concurrent conditions such as diabetes, obesity, and kidney dysfunction with SARS-CoV-2 infection further complicates the disease's impact on bone health. SARS-CoV-2 infection directly and indirectly affects bone health, leading to potential long-term consequences. This review article is part of a series of multiple manuscripts designed to determine the utility of using artificial intelligence for writing scientific reviews.

COVID-19 and Bone Loss: A Review of Risk Factors, Mechanisms, and Future Directions

PURPOSE OF REVIEW

SARS-CoV-2 drove the catastrophic global phenomenon of the COVID-19 pandemic resulting in a multitude of systemic health issues, including bone loss. The purpose of this review is to summarize recent findings related to bone loss and potential mechanisms.

RECENT FINDINGS

The early clinical evidence indicates an increase in vertebral fractures, hypocalcemia, vitamin D deficiencies, and a loss in BMD among COVID-19 patients. Additionally, lower BMD is associated with more severe SARS-CoV-2 infection. Preclinical models have shown bone loss and increased osteoclastogenesis. The bone loss associated with SARS-CoV-2 infection could be the result of many factors that directly affect the bone such as higher inflammation, activation of the NLRP3 inflammasome, recruitment of Th17 cells, the hypoxic environment, and changes in RANKL/OPG signaling. Additionally, SARS-CoV-2 infection can exert indirect effects on the skeleton, as mechanical unloading may occur with severe disease (e.g., bed rest) or with BMI loss and muscle wasting that has also been shown to occur with SARS-CoV-2 infection. Muscle wasting can also cause systemic issues that may influence the bone. Medications used to treat SARS-CoV-2 infection also have a negative effect on the bone. Lastly, SARS-CoV-2 infection may also worsen conditions such as diabetes and negatively affect kidney function, all of which could contribute to bone loss and increased fracture risk. SARS-CoV-2 can negatively affect the bone through multiple direct and indirect mechanisms. Future work will be needed to determine what patient populations are at risk of COVID-19-related increases in fracture risk, the mechanisms behind bone loss, and therapeutic options. This review article is part of a series of multiple manuscripts designed to determine the utility of using artificial intelligence for writing scientific reviews.

Parameterization of asymmetric sigmoid functions in weighted gene co-expression network analysis

In most the biological contexts, examining gene expressions at the genomic level gives more accurate results than examining genes individually. It can improve understanding of the molecular mechanisms that cause molecular alterations. Weighted gene co-expression network analysis (WGCNA), which has recently been widely used to cluster transcriptomic datasets, implements a soft thresholding procedure using power function. However, these functions may sometimes exaggerate minor differences in expression correlations. We have previously proposed to use asymmetric sigmoid functions in soft thresholding as an alternative solution. However, the number of variables in asymmetric sigmoid functions may vary and parameterization can be problematic. In this study, we have introduced a systematic procedure for parameterizing asymmetric sigmoid function to ease using it as an alternative soft-thresholding solution in WGCNA. The efficiency of the employment was shown on four different COVID-19 datasets, on a yeast dataset, and on an E.Coli dataset. The results indicate that this approach provides biologically plausible associations for the resulting modules.

Immune and metabolic perturbations in COVID-19-associated pulmonary mucormycosis: A transcriptome analysis of innate immune cells

BACKGROUND AND OBJECTIVES

The mechanisms underlying COVID-19-associated pulmonary mucormycosis (CAPM) remain unclear. We use a transcriptomic analysis of the innate immune cells to investigate the host immune and metabolic response pathways in patients with CAPM.

PATIENTS AND METHODS

We enrolled subjects with CAPM (n = 5), pulmonary mucormycosis (PM) without COVID-19 (n = 5), COVID-19 (without mucormycosis, n = 5), healthy controls (n = 5) without comorbid illness and negative for SARS-CoV-2. Peripheral blood samples from cases were collected before initiating antifungal therapy, and neutrophils and monocytes were isolated. RNA sequencing was performed using Illumina HiSeqX from monocytes and neutrophils. Raw reads were aligned with HISAT-2 pipeline and DESeq2 was used for differential gene expression. Gene ontology (GO) and metabolic pathway analysis were performed using Shiny GO application and R packages (ggplot2, Pathview).

RESULTS

The derangement of core immune and metabolic responses in CAPM patients was noted. Pattern recognition receptors, dectin-2, MCL, FcRγ receptors and CLEC-2, were upregulated, but signalling pathways such as JAK-STAT, IL-17 and CARD-9 were downregulated; mTOR and MAP-kinase signalling were elevated in monocytes from CAPM patients. The complement receptors, NETosis, and pro-inflammatory responses, such as S100A8/A9, lipocalin and MMP9, were elevated. The major metabolic pathways of glucose metabolism-glycolysis/gluconeogenesis, pentose phosphate pathway, HIF signalling and iron metabolism-ferroptosis were also upregulated in CAPM.

CONCLUSIONS

We identified significant alterations in the metabolic pathways possibly leading to cellular iron overload and a hyperglycaemic state. Immune responses revealed altered recognition, signalling, effector functions and a pro-inflammatory state in monocytes and neutrophils from CAPM patients.

Significance of monitoring the levels of thyroid hormone antibodies and glucose and lipid metabolism antibodies in patients suffer from type 2 diabetes

The association of thyroid hormone antibodies and glycolipid metabolism indicators with Type 2 diabetes mellitus (T2DM) was explored. As the disease worsens, the levels of thyroglobulin antibody (TGAb), thyroid peroxidase antibody (TPOAb), and thyroid-stimulating hormone (TSH) was increased, and the levels of total tri-iodothyronine (TT3) and total thyroxine (TT4) was decreased (P < 0.001). The severe, medium, and light group had higher level of high-density lipoprotein (HDL), lower level of total cholesterol (TC), low-density lipoprotein (LDL), glycosylated hemoglobin (HbA1c), triacylglycerol (TAG), and fasting blood sugar (FBG) than the control group (P ＜ 0.05). The level of HDL was lower in the severe group than the light group and the medium group, but the levels of TC, LDL, HbA1c, TAG, and FBG were increased with the progress of T2DM (P ＜ 0.001). The levels of TGAb, TPOAb, and TSH in patients with T2DM were positively correlated with the levels of TC, LDL, HbA1c, TAG, and FBG (P < 0.05), and were negatively correlated with HDL levels (P < 0.05). The life quality score was lower in the severe group than the light and the medium group (P < 0.001). Among the above indicators, the predictive value of TT3, TT4, and HbA1c in T2DM was better. Clinically, detecting the levels of thyroid hormone antibodies and glycolipid metabolism indicators had a certain predictive value for the severity of T2DM. Main findings: The results of this study found that the thyroid hormone antibody and glycolipid metabolism levels in T2DM patients were abnormal, and had different degrees of impact on the quality of life of patients. Thus, monitoring these indicators had certain predictive value for the severity of the disease, and also had a certain degree of suggestive effect on the evaluation of diabetic vascular complications. Clinically, attention should be paid to the screening of thyroid disease in diabetic patients, and the assessment and prognosis of thyroid function on diabetes, the control of diabetes, and the prevention and treatment of complications have important clinical significance.

Understanding COVID-19 progression with longitudinal peripheral blood mononuclear cell proteomics: Changes in the cellular proteome over time

The clinical presentation of COVID-19 is highly variable, and understanding the underlying biological processes is crucial. This study utilized a proteomic analysis to investigate dysregulated processes in the peripheral blood mononuclear cells of patients with COVID-19 compared to healthy volunteers. Samples were collected at different stages of the disease, including hospital admission, after 7 days of hospitalization, and 30 days after discharge. Metabolic pathway alterations and increased abundance of neutrophil-related proteins were observed in patients. Patients progressing to critical illness had significantly low-abundance proteins in the pentose phosphate and glycolysis pathways compared with those presenting clinical recovery. Important biological processes, such as fatty acid concentration and glucose metabolism disorder, remained altered even after 30 days of hospital discharge. Temporal proteomic changes revealed distinct pathways in critically ill and non-critically ill patients. Our study emphasizes the significance of longitudinal cellular proteomic studies in identifying disease progression-related pathways and persistent protein changes post-hospitalization.

Type 2 diabetes and Covid-19: Lessons learnt, unanswered questions and hints for the future

Type 2 diabetes (T2DM) and COVID-19 represent a considerable burden of disease for patients and healthcare systems. New evidence is transpiring detailing the existence of a bidirectional relationship between T2DM and COVID-19. Alongside the acute influence of pre-existing T2DM on the course of COVID-19 and the exacerbation of dysglycemia following acute infection, long-term sequalae resulting from the synergistic interplay between the two is emerging, namely the development of COVID-induced diabetes and long-COVID in patients with pre-existing diabetes. This review presents our current understanding of the bidirectionality between these two conditions with a view to highlighting questions which remain unanswered and suggesting avenues for future research. In doing so, it emphasises critical gaps where concentrated research efforts are likely to yield the most beneficial improvements in understanding of the relationship between the two conditions, translating to tangible optimisations in care for the affected population.

Psychophysical therapy and underlying neuroendocrine mechanisms for the rehabilitation of long COVID-19

With the global epidemic and prevention of the COVID-19, long COVID-19 sequelae and its comprehensive prevention have attracted widespread attention. Long COVID-19 sequelae refer to that three months after acute COVID-19, the test of SARS-CoV-2 is negative, but some symptoms still exist, such as cough, prolonged dyspnea and fatigue, shortness of breath, palpitations and insomnia. Its pathological mechanism is related to direct viral damage, immunopathological response, endocrine and metabolism disorders. Although there are more effective methods for treating COVID-19, the treatment options available for patients with long COVID-19 remain quite limited. Psychophysical therapies, such as exercise, oxygen therapy, photobiomodulation, and meditation, have been attempted as treatment modalities for long COVID-19, which have the potential to promote recovery through immune regulation, antioxidant effects, and neuroendocrine regulation. Neuroendocrine regulation plays a significant role in repairing damage after viral infection, regulating immune homeostasis, and improving metabolic activity in patients with long COVID-19. This review uses oxytocin as an example to examine the neuroendocrine mechanisms involved in the psychophysical therapies of long COVID-19 syndrome and proposes a psychophysical strategy for the treatment of long COVID-19.

Metabolomic Profile, Plasmatic Levels of Losartan and EXP3174, Blood Pressure Control in Hypertensive Patients and Their Correlation with COVID-19

Systemic arterial hypertension (SAH) is one of the most prevalent chronic diseases worldwide and is related to serious health complications. It has been pointed out as a major risk factor for COVID-19. This study aimed to determine the impact of COVID-19 on the metabolomic profile, the correlation with the plasmatic levels of losartan and its active metabolite (EXP3174), biochemical markers, and blood pressure (BP) control in hypertensive patients. 1H NMR metabolomic profiles of hypertensive and normotensive patients with and without previous COVID-19 diagnosis were identified. Plasmatic levels of LOS and EXP3174 were correlated with BP, biochemical markers, and the metabolomic fingerprint of the groups. Biomarkers linked to important aspects of SAH and COVID-19 were identified, such as glucose, glutamine, arginine, creatinine, alanine, choline, erythritol, homogentisate, 0-tyrosine, and 2-hydroxybutyrate. Those metabolites are indicative of metabolic alterations, kidney damage, pulmonary dysfunction, and persistent inflammation, which can be found in both diseases. Some hypertensive patients did not reach the therapeutic levels of LOS and EXP3174, while the BP control was also limited among the normotensive patients with previous COVID-19 diagnoses. Metabolomics proved to be an important tool for assessing the effectiveness of losartan pharmacotherapy and the damage caused by SAH and COVID-19 in hypertensive patients.

Associations of Serum Calprotectin, Arterial Stiffness and Long COVID Symptoms in Dalmatian Kidney Transplant Recipients

We aimed to explore long COVID symptoms, serum calprotectin levels, and the parameters of arterial stiffness in Dalmatian kidney transplant recipients (KTRs) and their possible associations. A cross-sectional, single-center case-control study on 98 KTRs who had recovered from COVID-19 was performed. Long COVID symptoms were explored via standardized questionnaires assessing quality of life, and serum calprotectin was also measured. Out of 98 KTRs with a mean age of 62 years, 63 (64.3%) were men. Medical history, clinical and laboratory parameters, and arterial stiffness measurements were obtained for each study participant. Difficulties with mobility were present in 44.3% of the KTRs, while difficulties with self-care were present in 6.2%, difficulties with usual activities were demonstrated by 35.1%, pain in the extremities was present in 52.5%, and anxiety and depression were present in 26.8%. Our results showed significant differences regarding serum calprotectin levels in clinical manifestations of acute COVID-19 and follow-up laboratory parameters. The most significant positive predictors of the serum calprotectin value in the KTRs were respiratory insufficiency, acute kidney failure, the prescription of antihypertensives, leukocyte and neutrophil counts, the neutrophil/lymphocyte ratio and lactate dehydrogenase levels. Negative predictors were the time since COVID-19, high-density lipoprotein levels, kidney function parameters, and the lymphocyte count. To conclude, serum calprotectin has emerged as a possible promising biomarker for subclinical allograft rejection; however, further studies are needed to better understand this subject.

[Impact of hyperglycemia on the prognosis of patients hospitalized for severe pneumonia in COVID-19]

Background

Adequate glycemic control improves the prognosis of patients hospitalized for pneumonia associated with severe COVID-19.

Objective

To evaluate the impact of hyperglycemia (HG) on the prognosis of patients hospitalized for severe pneumonia associated with COVID-19 in unvaccinated patients.

Material and methods

Prospective cohort study. We included patients hospitalized from August 2020 to February 2021, with severe COVID-19 pneumonia, not vaccinated against SARS-CoV-2. Data was collected from admission to discharge. We used descriptive and analytical statistics according to the data distribution. ROC curves were used to determine the cut-off points with the highest predictive performance for HG and mortality, with the IBM SPSS program, version 25.

Results

We included 103 patients, 32% women, 68% men, age 57 ± 13 years; 58% were admitted with HG (191, IQR 152-300 mg/dL) and 42% with normoglycemia (NG < 126 mg/dL). Mortality was higher in HG at admission 34 (56.7%) than in NG 13 (30.2%) (p = 0.008). HG was associated with diabetes mellitus 2 and neutrophilia (p < 0.05). The risk of death increases 1.558 times (95% CI 1.118-2.172) if HG is at admission and 1.43 times (95% CI 1.14-1.79) during hospitalization. Maintaining NG throughout the hospitalization contributed independently to survival (RR = 0.083 [95% CI 0.012-0.571], p = 0.011).

Conclusion

HG significantly impacts prognosis by increasing mortality more than 50% during hospitalization for COVID-19.

The COVID-19 Pandemic: SARS-CoV-2 Structure, Infection, Transmission, Symptomology, and Variants of Concern

Since it was first detected in December 2019, the COVID-19 pandemic has spread across the world and affected virtually every country and territory. The pathogen driving this pandemic is SARS-CoV-2, a positive-sense single-stranded RNA virus which is primarily transmissible though the air and can cause mild to severe respiratory infections in humans. Within the first year of the pandemic, the situation worsened with the emergence of several SARS-CoV-2 variants. Some of these were observed to be more virulent with varying capacities to escape the existing vaccines and were, therefore, denoted as variants of concern. This chapter provides a general overview of the course of the COVID-19 pandemic up to April 2022 with a focus on the structure, infection, transmission, and symptomology of the SARS-CoV-2 virus. The main objectives were to investigate the effects of the variants of concern on the trajectory of the virus and to highlight a potential pathway for coping with the current and future pandemics.

COVID-19 and Diabetes Mellitus: From Pathophysiology to Clinical Management

An increase in the severity of the coronavirus disease 2019 (COVID-19) was observed in patients infected with the acute severe metabolism syndrome coronavirus type 2 (SARS-CoV-2). Patients who have COVID-19 infection may also be more susceptible to hyperglycemia. When paired with other risk factors, hyperglycemia might alter immune and inflammatory responses, predisposing people to significant COVID-19 and perhaps deadly outcomes. Angiotensin-converting accelerator 2 (ACE2), a component of the renin-angiotensin-aldosterone system (RAAS), is the principal entry receptor for SARS-CoV-2; nevertheless, dipeptidyl enzyme 4 (DPP4) may potentially serve as a binding target. However, preliminary data did not indicate a substantial effect on the susceptibility to SARS-CoV-2 using glucose-lowering DPP4 inhibitors. Because of their pharmacologic characteristics, salt-glucose cotransporter 2 (SGLT2) inhibitors should not be advised for COVID-19 patients because they may have adverse effects. Currently, taking a hypoglycemic drug should be the most efficient way to manage acute glycemia. The majority of market proof is said to categorize two diabetes mellitus (DM) and fails to distinguish between the two primary categories of DM due to its widespread use. For grouping one DM and COVID-19, there is now some constrained proof available. Most of those findings are just preliminary, so further research will undoubtedly be required to determine the best course of action for DM patients.

1H qNMR-Based Metabolomics Discrimination of Covid-19 Severity

The coronavirus disease 2019 (Covid-19), which caused respiratory problems in many patients worldwide, led to more than 5 million deaths by the end of 2021. Experienced symptoms vary from mild to severe illness. Understanding the infection severity to reach a better prognosis could be useful to the clinics, and one study area to fulfill one piece of this biological puzzle is metabolomics. The metabolite profile and/or levels being monitored can help predict phenotype properties. Therefore, this study evaluated plasma metabolomes of 110 individual samples, 57 from control patients and 53 from recent positive cases of Covid-19 (IgM 98% reagent), representing mild to severe symptoms, before any clinical intervention. Polar metabolites from plasma samples were analyzed by quantitative 1H NMR. Glycerol, 3-aminoisobutyrate, formate, and glucuronate levels showed alterations in Covid-19 patients compared to those in the control group (Tukey's HSD p-value cutoff = 0.05), affecting the lactate, phenylalanine, tyrosine, and tryptophan biosynthesis and d-glutamine, d-glutamate, and glycerolipid metabolisms. These metabolic alterations show that SARS-CoV-2 infection led to disturbance in the energetic system, supporting the viral replication and corroborating with the severe clinical conditions of patients. Six polar metabolites (glycerol, acetate, 3-aminoisobutyrate, formate, glucuronate, and lactate) were revealed by PLS-DA and predicted by ROC curves and ANOVA to be potential prognostic metabolite panels for Covid-19 and considered clinically relevant for predicting infection severity due to their straight roles in the lipid and energy metabolism. Thus, metabolomics from samples of Covid-19 patients is a powerful tool for a better understanding of the disease mechanism of action and metabolic consequences of the infection in the human body and may corroborate allowing clinicians to intervene quickly according to the needs of Covid-19 patients.

Vitamin D: A Role Also in Long COVID-19?

Coronavirus disease 2019 (COVID-19) has quickly become a global pandemic. Reports from different parts of the world indicate that a significant proportion of people who have recovered from COVID-19 are suffering from various health problems collectively referred to as “long COVID-19”. Common symptoms include fatigue, shortness of breath, cough, joint pain, chest pain, muscle aches, headaches, and so on. Vitamin D is an immunomodulatory hormone with proven efficacy against various upper respiratory tract infections. Vitamin D can inhibit hyperinflammatory reactions and accelerate the healing process in the affected areas, especially in lung tissue. Moreover, vitamin D deficiency has been associated with the severity and mortality of COVID-19 cases, with a high prevalence of hypovitaminosis D found in patients with COVID-19 and acute respiratory failure. Thus, there are promising reasons to promote research into the effects of vitamin D supplementation in COVID-19 patients. However, no studies to date have found that vitamin D affects post-COVID-19 symptoms or biomarkers. Based on this scenario, this review aims to provide an up-to-date overview of the potential role of vitamin D in long COVID-19 and of the current literature on this topic.

The "identikit" of subject with obesity and COVID-19 vaccine breakthrough

The mRNA coronavirus disease 2019 (COVID-19) vaccines were highly effective in the prevention of symptomatic COVID-19, hospitalization, severe disease, and death. However, a minority of vaccinated individuals might become infected and experience significant morbidity. Risk factors of COVID-19 vaccine breakthrough in obesity have not been elucidated. Thus, we aimed to portray the subjects with obesity developing COVID-19 vaccine breakthrough despite vaccination. Coronavirus 2019 (COVID-19) mRNA vaccines have been highly effective in preventing symptomatic COVID-19, hospitalization, severe illness and death. However, a minority of vaccinated individuals may become infected and experience considerable morbidity. The risk factors for COVID-19 vaccine breakthrough in obesity have not been elucidated. Therefore, we aimed to depict individuals with obesity who develop COVID-19 vaccine breakthrough despite vaccination. An online questionnaire was distributed to respondents via a snowball sampling method among subjects with obesity belonging to Italian Associations for people living with obesity aged 18 years and above. Two hundred and thirty-five respondents (44.5±14 years; BMI: 33.3±7.2 kg/m²) were included in the study. COVID-19 vaccine breakthrough was noted in 34 % of respondents. A higher prevalence of grade III obesity was detected in subjects with COVID-19 vaccine breakthrough compared to subjects that did not (27.5 % vs 13.5 %; p=0.014). In addition, a significant lower prevalence of respondents that completed third dose were found in respondents with COVID-19 vaccine breakthrough compared with respondents that did not develop it (33.8 % vs 72.9 %; p<0.001). After stratifying respondents with COVID-19 vaccine breakthrough according to the completed doses of vaccine, we found that, although no differences were detected in terms of clinical manifestations of COVID-19, there was a significant higher prevalence of type 2 diabetes and hypertension in respondents that completed third doses compared to respondents that completed first and second doses. In conclusion, COVID-19 vaccine breakthrough was more common in subjects with grade III obesity. The presence of type 2 diabetes and hypertension could counteract the immune potentiating effects of vaccine booster against COVID-19.

Low-grade inflammation, CoVID-19, and obesity: clinical aspect and molecular insights in childhood and adulthood

The new 2019 coronavirus 19 disease (CoVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a serious threat to health systems. As a global health problem, this pandemic poses a huge threat to people and is responsible for significant morbidity and mortality worldwide. On the other hand, obesity has also reached epidemic proportions and poses another challenge to the healthcare system. There is increasing evidence of a strong association between obesity and CoVID-19 disease, but the mechanisms underlying the link between the two remain unclear and the role of obesity also remains to be elucidated. In particular obesity-related low-grade inflammation has been hypothesized as the Achille's heel that could predispose subjects with obesity to a more severe CoVID-19 compared to subjects with normal weight. Hence, we summarized recent evidence on the role of low-grade inflammation in clinical aspects of CoVID-19 in subjects with obesity in both childhood and adulthood. Further, we provide molecular insights to explain this link.

The Effects of Increased Glucose Level and the Role of Glycolysis on SARS CoV-2 Infection

Abstract:

Covid-19 has entered our lives for a long time as an infection with high mortality rates. Although the vaccination process has provided benefits, the death toll remains to be frightening worldwide. Therefore, drugs and combined therapies that can be used against Covid-19 infection are still being investigated. Most of these antiviral medications are investigational drug candidates which are still in clinical trials. In this context, holistic and different approaches for the treatment of Covid-19 including prophylactic use of natural medicines are under investigation and may offer potential treatment options due to the fact that this is still an unmet medical need in the world. Thus, inhibiting the increased glycolysis on Covid-19 infection with glycolysis inhibitors may be beneficial for patient survival. This short review highlights the potential benefits of glycolysis inhibition as well as controlling the elevated glucose levels in patients with the treatment of Covid-19.

Hyperglycemia and Loss of Redox Homeostasis in COVID-19 Patients

The infection with SARS-CoV-2 impairs the glucose−insulin axis and this contributes to oxidative (OS) and nitrosative (NSS) stress. Here, we evaluated changes in glucose metabolism that could promote the loss of redox homeostasis in COVID-19 patients. This was comparative cohort and analytical study that compared COVID-19 patients and healthy subjects. The study population consisted of 61 COVID-19 patients with and without comorbidities and 25 healthy subjects (HS). In all subjects the plasma glucose, insulin, 8-isoprostane, Vitamin D, H2S and 3-nitrotyrosine were determined by ELISA. The nitrites (NO2−), lipid-peroxidation (LPO), total-antioxidant-capacity (TAC), thiols, glutathione (GSH) and selenium (Se) were determined by spectrophotometry. The glucose, insulin and HOMA-IR (p < 0.001), 8-isoprostanes, 3-nitrotyrosine (p < 0.001) and LPO were increased (p = 0.02) while Vitamin D (p = 0.01), H2S, thiols, TAC, GSH and Se (p < 0.001) decreased in COVID-19 patients in comparison to HS. The SARS-CoV-2 infection resulted in alterations in the glucose−insulin axis that led to hyperglycemia, hyperinsulinemia and IR in patients with and without comorbidities. These alterations increase OS and NSS reflected in increases or decreases in some oxidative markers in plasma with major impact or fatal consequences in patients that course with metabolic syndrome. Moreover, subjects without comorbidities could have long-term alterations in the redox homeostasis after infection.

Cellular metabolic basis of altered immunity in the lungs of patients with COVID-19

Metabolic pathways drive cellular behavior. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes lung tissue damage directly by targeting cells or indirectly by producing inflammatory cytokines. However, whether functional alterations are related to metabolic changes in lung cells after SARS-CoV-2 infection remains unknown. Here, we analyzed the lung single-nucleus RNA-sequencing (snRNA-seq) data of several deceased COVID-19 patients and focused on changes in transcripts associated with cellular metabolism. We observed upregulated glycolysis and oxidative phosphorylation in alveolar type 2 progenitor cells, which may block alveolar epithelial differentiation and surfactant secretion. Elevated inositol phosphate metabolism in airway progenitor cells may promote neutrophil infiltration and damage the lung barrier. Further, multiple metabolic alterations in the airway goblet cells are associated with impaired muco-ciliary clearance. Increased glycolysis, oxidative phosphorylation, and inositol phosphate metabolism not only enhance macrophage activation but also contribute to SARS-CoV-2 induced lung injury. The cytotoxicity of natural killer cells and CD8⁺ T cells may be enhanced by glycerolipid and inositol phosphate metabolism. Glycolytic activation in fibroblasts is related to myofibroblast differentiation and fibrogenesis. Glycolysis, oxidative phosphorylation, and glutathione metabolism may also boost the aging, apoptosis and proliferation of vascular smooth muscle cells, resulting in pulmonary arterial hypertension. In conclusion, this preliminary study revealed a possible cellular metabolic basis for the altered innate immunity, adaptive immunity, and niche cell function in the lung after SARS-CoV-2 infection. Therefore, patients with COVID-19 may benefit from therapeutic strategies targeting cellular metabolism in future.

COVID-19 and diabetes-Two giants colliding: From pathophysiology to management

Since December 2019, a new coronavirus, called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread around the world, causing the coronavirus 2019 (COVID-19) pandemic. From the beginning, SARS-CoV-2 has put a strain on the health system. In fact, many patients have had severe forms of the disease with the need for hospitalization due to respiratory failure. To contain the pandemic, the most widely used approach has been lockdowns. Social restrictions have been reduced thanks to the development of vaccines and targeted therapies. However, fatal events still occur among people at high risk of serious infection, such as patients with concomitant diabetes. Different mechanisms have been proposed to explain the poor prognosis of patients with diabetes and COVID-19, but the specific cause is unclear. It is now known that insulin resistance, inflammation, and cytokine storm are involved. Moreover, SARS-CoV-2 uses the angiotensin-converting enzyme 2 receptors to enter cells. This receptor is expressed on pancreatic beta cells and, during infection, it appears that receptor involvement may induce hyperglycemia in patients with or without diabetes. In this study, we discuss the mechanisms underlying the poor prognosis in people with COVID-19 and diabetes and what may improve the outcome in these patients.

The Triangle Relationship Between Long Noncoding RNA, RIG-I-like Receptor Signaling Pathway, and Glycolysis

Long noncoding RNA (LncRNA), a noncoding RNA over 200nt in length, can regulate glycolysis through metabolic pathways, glucose metabolizing enzymes, and epigenetic reprogramming. Upon viral infection, increased aerobic glycolysis providzes material and energy for viral replication. Mitochondrial antiviral signaling protein (MAVS) is the only protein-specified downstream of retinoic acid-inducible gene I (RIG-I) that bridges the gap between antiviral immunity and glycolysis. MAVS binding to RIG-I inhibits MAVS binding to Hexokinase (HK2), thereby impairing glycolysis, while excess lactate production inhibits MAVS and the downstream antiviral immune response, facilitating viral replication. LncRNAs can also regulate antiviral innate immunity by interacting with RIG-I and downstream signaling pathways and by regulating the expression of interferons and interferon-stimulated genes (ISGs). Altogether, we summarize the relationship between glycolysis, antiviral immunity, and lncRNAs and propose that lncRNAs interact with glycolysis and antiviral pathways, providing a new perspective for the future treatment against virus infection, including SARS-CoV-2.

Targeting the Pentose Phosphate Pathway for SARS-CoV-2 Therapy

SARS-CoV-2 is causing the coronavirus disease 2019 (COVID-19) pandemic, for which effective pharmacological therapies are needed. SARS-CoV-2 induces a shift of the host cell metabolism towards glycolysis, and the glycolysis inhibitor 2-deoxy-d-glucose (2DG), which interferes with SARS-CoV-2 infection, is under development for the treatment of COVID-19 patients. The glycolytic pathway generates intermediates that supply the non-oxidative branch of the pentose phosphate pathway (PPP). In this study, the analysis of proteomics data indicated increased transketolase (TKT) levels in SARS-CoV-2-infected cells, suggesting that a role is played by the non-oxidative PPP. In agreement, the TKT inhibitor benfooxythiamine (BOT) inhibited SARS-CoV-2 replication and increased the anti-SARS-CoV-2 activity of 2DG. In conclusion, SARS-CoV-2 infection is associated with changes in the regulation of the PPP. The TKT inhibitor BOT inhibited SARS-CoV-2 replication and increased the activity of the glycolysis inhibitor 2DG. Notably, metabolic drugs like BOT and 2DG may also interfere with COVID-19-associated immunopathology by modifying the metabolism of immune cells in addition to inhibiting SARS-CoV-2 replication. Hence, they may improve COVID-19 therapy outcomes by exerting antiviral and immunomodulatory effects.

Fasting plasma glucose and glucose fluctuation are associated with COVID-19 prognosis regardless of pre-existing diabetes

AIMS

We aimed to investigate the role of Fasting Plasma Glucose (FPG) and glucose fluctuation in the prognosis of COVID-19 patients stratified by pre-existing diabetes.

METHODS

The associations of FPG and glucose fluctuation indexes with prognosis of COVID-19 in 2,642 patients were investigated by multivariate Cox regression analysis. The primary outcome was in-hospital mortality; the secondary outcome was disease progression. The longitudinal changes of FPG over time were analyzed by the latent growth curve model in COVID-19 patients stratified by diabetes and severity of COVID-19.

RESULTS

We found FPG as an independent prognostic factor of overall survival after adjustment for age, sex, diabetes and severity of COVID-19 at admission (HR: 1.15, 95% CI: 1.06-1.25, P = 1.02 × 10^-3). Multivariate logistic regression analysis indicated that the standard deviation of blood glucose (SDBG) and largest amplitude of glycemic excursions (LAGE) were also independent risk factors of COVID-19 progression (P = 0.03 and 0.04, respectively). The growth trajectory of FPG over the first 3 days of hospitalization was steeper in patients with critical COVID-19 in comparison to moderate patients.

CONCLUSIONS

Hyperglycemia and glucose fluctuation were adverse prognostic factors of COVID-19 regardless of pre-existing diabetes. This stresses the importance of glycemic control in addition to other therapeutic management.