Sigma-1 Receptor Signaling: In Search of New Therapeutic Alternatives for Cardiovascular and Renal Diseases.

Cardiovascular and renal diseases are among the leading causes of death worldwide, and regardless of current efforts, there is a demanding need for therapeutic alternatives to reduce their progression to advanced stages. The stress caused by diseases leads to the activation of protective mechanisms in the cell, including chaperone proteins. The Sigma-1 receptor (Sig-1R) is a ligand-operated chaperone protein that modulates signal transduction during cellular stress processes. Sig-1R interacts with various ligands and proteins to elicit distinct cellular responses, thus, making it a potential target for pharmacological modulation. Furthermore, Sig-1R ligands activate signaling pathways that promote cardioprotection, ameliorate ischemic injury, and drive myofibroblast activation and fibrosis. The role of Sig-1R in diseases has also made it a point of interest in developing clinical trials for pain, neurodegeneration, ischemic stroke, depression in patients with heart failure, and COVID-19. Sig-1R ligands in preclinical models have significantly beneficial effects associated with improved cardiac function, ventricular remodeling, hypertrophy reduction, and, in the kidney, reduced ischemic damage. These basic discoveries could inform clinical trials for heart failure (HF), myocardial hypertrophy, acute kidney injury (AKI), and chronic kidney disease (CKD). Here, we review Sig-1R signaling pathways and the evidence of Sig-1R modulation in preclinical cardiac and renal injury models to support the potential therapeutic use of Sig-1R agonists and antagonists in these diseases.

Diffuse proliferative glomerulonephritis in a patient with COVID-19 infection.

COVID-19 primarily presents with respiratory involvement. Extrapulmonary manifestations as the sole manifestation also occur although rare. The kidney, being one of the organs with the greatest number of ACE receptors, is usually reported as part of multiorgan involvement. We report an early adolescent boy who presented with nephrotic-nephritic syndrome with severe kidney dysfunction from COVID-19 infection. He had low C3 and undetected antineutrophil cytoplasmic antibodies, antinuclear antibody and antistreptolysin O. Kidney biopsy revealed findings consistent with diffuse proliferative glomerulonephritis with a focal glomerular crescent formation and thin basement nephropathy. Due to the rapidly progressive deterioration of kidney function, he was given pulse methylprednisolone therapy followed by oral prednisone. Complete recovery was documented 12 weeks after the onset of post-infectious glomerulonephritis. The possible pathogenesis of glomerulonephritis in a patient with COVID-19, its differential diagnosis and treatment are discussed.

Relapse of cryoglobulinemic vasculitis with new-onset severe renal involvement in two patients following mRNA COVID-19 vaccination: A case report.

RATIONALE: Since mass-scale severe acute respiratory syndrome coronavirus 2 vaccination, there have been case reports of several immune-mediated reactions, including new-onset and flares of glomerular disorders following immunization with mRNA coronavirus disease 2019 vaccines. Here, we report two cases, the first to our knowledge, of relapsing cryoglobulinemic vasculitis with new-onset severe renal involvement following mRNA coronavirus disease 2019 vaccination. PATIENT CONCERNS: The relapse of the cutaneous and the new onset of severe renal involvement of cryoglobulinemic vasculitis occurred three weeks after the second dose of the mRNA Moderna coronavirus disease 2019 vaccination and two days after the first dose of mRNA Pfizer coronavirus disease 2019 vaccination in the first and second patient, respectively. DIAGNOSIS: Kidney biopsies were performed. The first pacient's kidney biopsy showed a membranoproliferative pattern of glomerular injury with extensive mesangial and endocapillary hypercellularity, while severe endothelial swelling, loss of fenestrations and widening of subendothelial space were identified by electron-microscopy. The second patient's kidney biopsy was consistent with cryoglobulin associated membrano-proliferative pattern of glomerular injury. INTERVENTIONS: Our patients were managed with a combination of immunosuppressants consisting of corticosteroids, Cyclophosphamide and Rituximab with a favourable outcome at the end of the induction period. OUTCOMES: Clinical and immunological response was achieved in both patients after four months of follow-up. LESSONS: The temporal association of the relapse of the cryoglobulinemic vasculitis to mRNA coronavirus disease 2019 vaccination suggest that the vaccine might have been a trigger for the reactivation of the disease in our cases. This possible association should be acknowledged by physicians in order to provide optimal monitoring and treatment in case of reactivation of the disease post-immunization.

Olfactory dysfunction in COVID-19, new insights from a cohort of 353 patients: The ANOSVID study.

Olfactory disorders (OD) pathogenesis, underlying conditions, and prognostic in coronavirus disease 2019 (COVID-19) remain partially described. ANOSVID is a retrospective study in Nord Franche-Comté Hospital (France) that included COVID-19 patients from March 1 2020 to May 31 2020. The aim was to compare COVID-19 patients with OD (OD group) and patients without OD (no-OD group). A second analysis compared patients with anosmia (high OD group) and patients with hyposmia or no OD (low or no-OD group). The OD group presented less cardiovascular and other respiratory diseases compared to the no-OD group (odds ratio [OR] = 0.536 [0.293-0.981], p = 0.041 and OR = 0.222 [0.056-0.874], p = 0.037 respectively). Moreover, history of malignancy was less present in the high OD group compared with the low or no-OD group (OR = 0.170 [0.064-0.455], p < 0.001). The main associated symptoms (OR > 5) with OD were loss of taste (OR = 24.059 [13.474-42.959], p = 0.000) and cacosmia (OR = 5.821 [2.246-15.085], p < 0.001). Most of all ORs decreased in the second analysis, especially for general, digestive, and ENT symptoms. Only two ORs increased: headache (OR = 2.697 [1.746-4.167], p < 0.001) and facial pain (OR = 2.901 [1.441-5.842], p = 0.002). The high OD group had a higher creatinine clearance CKD than the low or no-OD group (89.0 ± 21.1 vs. 81.0 ± 20.5, p = 0.040). No significant difference was found concerning the virological, radiological, and severity criteria. OD patients seem to have less comorbidity, especially better cardiovascular and renal function. Associated symptoms with OD were mostly neurological symptoms. We did not find a significant relationship between OD and less severity in COVID-19 possibly due to methodological bias.

Virus-related collapsing glomerulopathy, a common mechanism of injury?

Collapsing glomerulopathy frequently shows focal lesions on biopsy, creating challenges with transcriptomic investigations because of inadequate tissue sample. This challenge is overcome with spatial transcriptomics, technology linking transcriptomic data to histology. Applying this technology to investigate patients with collapsing glomerulopathy related to HIV infection or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), Smith et al. provide provocative evidence that collapsing glomerulopathy may have different molecular signatures despite the similar morphologic appearance.

Chain Mediation Model of Perceived Stress, Resilience, and Social Support on Coping Styles of Chinese Patients on Hemodialysis During COVID-19 Pandemic Lockdown.

BACKGROUND The recurrence of COVID-19 and the continuous escalation of prevention and control policies can lead to an increase in mental health problems. This study aimed to investigate the perceived stress, coping style, resilience, and social support among patients on maintenance hemodialysis (MHD) during the COVID-19 epidemic lockdown in China. MATERIAL AND METHODS This cross-sectional observational study enrolled 197 patients on MHD from the Guangdong Province Traditional Chinese Medical Hospital and the Hedong Hospital of Guangzhou Liwan District People's Hospital during July 2021. AMOS 24.0 and PROCESS Macro 3.1 model 6 were used for analyses of moderating mediating effects. RESULTS Perceived stress was negatively correlated with positive coping style (r=-0.305, P<0.001) and resilience (r=-0.258, P<0.001), whereas resilience (r=0.631, P<0.001) and social support (r=0.300, P<0.001) were positively correlated with positive coping style among patients on MHD. In the moderated mediating model, perceived stress had significant direct predictive effects on positive coping style (95% CI -0.33, -0.07), and perceived stress had significant indirect predictive effects on positive coping styles through resilience (95% CI -0.26, -0.06) or social support (95% CI 0.01, 0.06). Perceived stress had significant indirect predictive effects on positive coping style through both resilience and social support (95% CI -0.04, -0.01). CONCLUSIONS Perceived stress not only predicted coping style directly, but also indirectly predicted coping style through resilience and social support. Coping style was affected by internal and external factors during the COVID-19 pandemic lockdown period.

Spectrum of Kidney Injury Following COVID-19 Disease: Renal Biopsy Findings in a Single Italian Pathology Service.

The onset of coronavirus disease (COVID-19) as a pandemic infection, has led to increasing insights on its pathophysiology and clinical features being revealed, such as a noticeable kidney involvement. In this study, we describe the histopathological, immunofluorescence, and ultrastructural features of biopsy-proven kidney injury observed in a series of SARS-CoV-2 positive cases in our institution from April 2020 to November 2021. We retrieved and retrospectively reviewed nine cases (two pediatric and seven adults) that experienced nephrotic syndrome (six cases), acute kidney injury (two cases), and a clinically silent microhematuria and leukocyturia. Kidney biopsies were investigated by means of light microscopy, direct immunofluorescence, and electron microscopy. The primary diagnoses were minimal change disease (four cases), acute tubular necrosis (two cases), collapsing glomerulopathy (two cases), and C3 glomerulopathy (one case). None of the cases showed viral or viral-like particles on ultrastructural analysis. Novel and specific histologic features on kidney biopsy related to SARS-CoV-2 infection have been gradually disclosed and reported, harboring relevant clinical and therapeutic implications. Recognizing and properly diagnosing renal involvement in patients experiencing COVID-19 could be challenging (due to the lack of direct proof of viral infection, e.g., viral particles) and requires a proper integration of clinical and pathological data.

Characteristics, risk factors, and outcomes associated with readmission in COVID-19 patients: A systematic review and meta-analysis.

BACKGROUND: We aimed to determine the characteristics, risk factors, and outcomes associated with readmission in COVID-19 patients. METHODS: PubMed, Embase, Web of Science, and Scopus databases were searched to retrieve articles on readmitted COVID-19 patients, available up to September 25, 2021. All studies comparing characteristics of readmitted and non-readmitted COVID-19 patients were included. We also included articles reporting the reasons for readmission in COVID-19 patients. Data were pooled and meta-analyzed using random or fixed-effect models, as appropriate. Subgroup analyses were conducted based on the place and duration of readmission. RESULTS: Our meta-analysis included 4823 readmitted and 63,413 non-readmitted COVID-19 patients. The re-hospitalization rate was calculated at 9.3% with 95% Confidence Interval (CI) [5.5%-15.4%], mostly associated with respiratory or cardiac complications (48% and 14%, respectively). Comorbidities including cerebrovascular disease (Odds Ratio (OR) = 1.812; 95% CI [1.547-2.121]), cardiovascular (2.173 [1.545-3.057]), hypertension (1.608 [1.319-1.960]), ischemic heart disease (1.998 [1.495-2.670]), heart failure (2.556 [1.980-3.300]), diabetes (1.588 [1.443-1.747]), cancer (1.817 [1.526-2.162]), kidney disease (2.083 [1.498-2.897]), chronic pulmonary disease (1.601 [1.438-1.783]), as well as older age (1.525 [1.175-1.978]), male sex (1.155 [1.041-1.282]), and white race (1.263 [1.044-1.528]) were significantly associated with higher readmission rates (P < 0.05 for all instances). The mortality rate was significantly lower in readmitted patients (OR = 0.530 [0.329-0.855], P = 0.009). CONCLUSIONS: Male sex, white race, comorbidities, and older age were associated with a higher risk of readmission among previously admitted COVID-19 patients. These factors can help clinicians and policy-makers predict, and conceivably reduce the risk of readmission in COVID-19 patients.

Mechanisms of COVID-19-induced kidney injury and current pharmacotherapies.

The COVID-19 pandemic created a worldwide debilitating health crisis with the entire humanity suffering from the deleterious effects associated with the high infectivity and mortality rates. While significant evidence is currently available online and targets various aspects of the disease, both inflammatory and noninflammatory kidney manifestations secondary to COVID-19 infection are still largely underrepresented. In this review, we summarized current knowledge about COVID-19-related kidney manifestations, their pathologic mechanisms as well as various pharmacotherapies used to treat patients with COVID-19. We also shed light on the effect of these medications on kidney functions that can further enhance renal damage secondary to the illness.

COVID-19 modeling and non-pharmaceutical interventions in an outpatient dialysis unit.

This paper describes a data-driven simulation study that explores the relative impact of several low-cost and practical non-pharmaceutical interventions on the spread of COVID-19 in an outpatient hospital dialysis unit. The interventions considered include: (i) voluntary self-isolation of healthcare personnel (HCPs) with symptoms; (ii) a program of active syndromic surveillance and compulsory isolation of HCPs; (iii) the use of masks or respirators by patients and HCPs; (iv) improved social distancing among HCPs; (v) increased physical separation of dialysis stations; and (vi) patient isolation combined with preemptive isolation of exposed HCPs. Our simulations show that under conditions that existed prior to the COVID-19 outbreak, extremely high rates of COVID-19 infection can result in a dialysis unit. In simulations under worst-case modeling assumptions, a combination of relatively inexpensive interventions such as requiring surgical masks for everyone, encouraging social distancing between healthcare professionals (HCPs), slightly increasing the physical distance between dialysis stations, and-once the first symptomatic patient is detected-isolating that patient, replacing the HCP having had the most exposure to that patient, and relatively short-term use of N95 respirators by other HCPs can lead to a substantial reduction in both the attack rate and the likelihood of any spread beyond patient zero. For example, in a scenario with R0 = 3.0, 60% presymptomatic viral shedding, and a dialysis patient being the infection source, the attack rate falls from 87.8% at baseline to 34.6% with this intervention bundle. Furthermore, the likelihood of having no additional infections increases from 6.2% at baseline to 32.4% with this intervention bundle.

Kidney involvement in COVID-19 and its treatments.

The lungs are the most commonly affected organ by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the kidneys are also frequently affected. Infection with SARS-CoV-2 can not only cause new kidney damage but also increase the difficulty of treatment and care as well as mortality for people with underlying kidney diseases. Kidney involvement in SARS-CoV-2 infection mainly manifests as kidney tubular injury. Proteinuria is the main clinical sign. To reduce patient mortality, kidney complications should be given increased attention in the diagnosis and treatment of coronavirus disease 2019 (COVID-19). This study reviews the existing literature and discusses COVID-19 infection in combination with kidney diseases in terms of kidney damage, pathogenesis, and treatment to guide clinical anti-epidemic responses.

Kidney transplant dysfunction in a patient with COVID - 19 infection: role of concurrent Sars-Cov 2 nephropathy, chronic rejection and vitamin C-mediated hyperoxalosis: case report.

BACKGROUND: COVID-19 infection in kidney transplant recipients often lead to allograft dysfunction. The allograft injury has various histopathological manifestations. Our case illustrates the unusual combination of allograft rejection, acute kidney injury secondary to oxalate nephropathy and SARS CoV-2 nephropathy as the cause of irreversible allograft failure. CASE PRESENTATION: A 56 year old renal allograft recipient presented with a history of fever and diarrhoea for the preceding 4 weeks, tested positive for Sars-CoV2 on nasal swab and was found to have severe allograft dysfunction, necessitating haemodialysis. He subsequently underwent an allograft biopsy, which demonstrated antibody mediated rejection along with the presence of extensive oxalate deposition in the tubules. Ultrastructural examination demonstrated spherical spiked particles in the glomerular capillary endothelium and the presence of tubulo-reticular inclusions suggestive of an active COVID-19 infection within the kidney. The intra-tubular oxalate deposition was considered to be the result of high dose, supplemental Vitamin C used as an immune booster in many patients with COVID - 19 infection in India. CONCLUSIONS: This case highlights the complex pathology that may be seen in following COVID-19 disease and the need for kidney biopsies in these patients to better understand the aetiology of disease.

Interaction between age and vitamin D deficiency in severe COVID-19 infection.

INTRODUCTION: Background: coronavirus disease 2019 (COVID-19) can induce an exaggerated inflammatory response. Vitamin D is a key modulator of the immune system. We hypothesized that vitamin D deficiency (VDD) could increase the risk of developing severe COVID-19 infection. Methods: patients with confirmed COVID-19 seen at the emergency department of our hospital with recent measurements of 25(OH)D were recruited. We explored the association of vitamin D deficiency (VDD), defined as 25-hydroxyvitamin D < 20 ng/mL, with a composite of adverse clinical outcomes. Results: we included 80 patients, of which 31 (39 %) presented the endpoint. VDD tended to predict an increased risk of developing severe COVID-19 after adjusting for age, gender, obesity, cardiac disease, and kidney disease [OR 3.2 (95 % CI: 0.9-11.4), p = 0.07]. Age had a negative interaction with the effect of VDD on the composite outcome (p = 0.03), indicating that the effect was more noticeable at younger ages. Furthermore, male gender was associated with VDD and with severe COVID-19 at younger ages. Conclusions: in this retrospective study, vitamin D deficiency showed a signal of association with severe COVID-19 infection. A significant interaction with age was noted, suggesting VDD may have a greater impact in younger patients. These findings should be confirmed in larger, prospective, adequately powered studies.

INTRODUCCIÓN: Antecedentes: la enfermedad por coronavirus 2019 (COVID-19) puede inducir una respuesta inflamatoria exagerada. La vitamina D es un modulador clave del sistema inmune. Planteamos que la deficiencia de vitamina D (VDD) podría aumentar el riesgo de desarrollar infección grave por COVID-19. Métodos: se reclutaron pacientes consecutivos que acudieron al servicio de urgencias de nuestro centro con diagnóstico de COVID-19 confirmado (PCR-COVID-19 positiva) y mediciones recientes de 25(OH)D. Exploramos la asociación de la deficiencia de vitamina D (VDD), definida como una 25-hidroxivitamina D < 20 ng/ml, con un compuesto de resultados clínicos adversos. Resultados: se incluyeron 80 pacientes, de los cuales 31 (39 %) presentaron el criterio de valoración primario. El VDD tendió a predecir un mayor riesgo de desarrollar COVID-19 grave después de ajustar edad, sexo, obesidad, enfermedad cardíaca y enfermedad renal [OR: 3,2 (IC 95 %: 0,9-11,4), p = 0,07]. La edad tuvo una interacción negativa con el efecto de la VDD en el resultado compuesto (p = 0,03), lo que indica que el efecto fue más notable a edades más tempranas. Además, el género masculino se asoció con la VDD y con la COVID-19 grave en las edades más jóvenes. Conclusiones: en este estudio retrospectivo, la deficiencia de vitamina D mostró una tendencia de asociación con la infección grave por COVID-19. Se observó una interacción significativa con la edad, lo que sugiere que la VDD puede tener un mayor impacto en los pacientes más jóvenes. Estos hallazgos deben confirmarse en estudios más grandes, prospectivos y con potencia adecuada.

Renal dysfunction and prognosis of COVID-19 patients: a hospital-based retrospective cohort study.

INTRODUCTION: Increasing evidence indicate that coronavirus disease 2019 (COVID-19) is companied by renal dysfunction. However, the association of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2)-induced renal dysfunction with prognosis remains obscure. MATERIALS AND METHODS: All 154 patients with COVID-19 were recruited from the Second People's Hospital of Fuyang City in Anhui, China. Demographic characteristics and laboratory data were extracted. Renal dysfunction was evaluated and its prognosis was followed up based on a retrospective cohort study. RESULTS: There were 125 (81.2%) mild and 29 (18.8%) severe cases in 154 COVID-19 patients. On admission, 16 (10.4%) subjects were accompanied with renal dysfunction. Serum creatinine and cystatin C were increased and estimated glomerular filtration rate (eGFR) was decreased in severe patients compared with those in mild patients. Renal dysfunction was more prevalent in severe patients. Using multivariate logistic regression, we found that male gender, older age and hypertension were three importantly independent risk factors for renal dysfunction in COVID-19 patients. Follow-up study found that at least one renal function marker of 3.33% patients remained abnormal in 2 weeks after discharge. CONCLUSION: Male elderly COVID-19 patients with hypertension elevates the risk of renal dysfunction. SARS-CoV-2-induced renal dysfunction are not fully recovered in 2 weeks after discharge.

Characteristics, comorbidities and survival analysis of young adults hospitalized with COVID-19 in New York City.

This study reviewed 395 young adults, 18-35 year-old, admitted for COVID-19 to one of the eleven hospitals in New York City public health system. Demographics, comorbidities, clinical course, outcomes and characteristics linked to hospitalization were analyzed including temporal survival analysis. Fifty-seven percent of patients had a least one major comorbidity. Mortality without comorbidity was in 3.8% patients. Further investigation of admission features and medical history was conducted. Comorbidities associated with mortality were diabetes (n = 54 deceased/73 diagnosed,74% tested POS;98.2% with diabetic history deceased; Wilcoxon p (Wp) = .044), hypertension (14/44,32% POS, 25.5%; Wp = 0.030), renal (6/16, 37.5% POS,11%; Wp = 0.000), and cardiac (6/21, 28.6% POS,11%; Wp = 0.015). Kaplan survival plots were statistically significant for these four indicators. Data suggested glucose >215 or hemoglobin A1c >9.5 for young adults on admission was associated with increased mortality. Clinically documented respiratory distress on admission was statistically significant outcome related to mortality (X2 = 236.6842, df = 1, p < .0001). Overall, 28.9% required supportive oxygen beyond nasal cannula. Nasal cannula oxygen alone was required for 71.1%, who all lived. Non-invasive ventilation was required for 7.8%, and invasive mechanical ventilation 21.0% (in which 7.3% lived, 13.7% died). Temporal survival analysis demonstrated statistically significant response for Time to Death <10 days (X2 = 18.508, df = 1, p = .000); risk lessened considerably for 21 day cut off (X2 = 3.464, df = 1, p = .063), followed by 31 or more days of hospitalization (X2 = 2.212, df = 1, p = .137).

COVID-19 and Renal Diseases: An Update.

BACKGROUND: It becomes increasingly evident that the SARS-CoV-2 infection is not limited to the respiratory system. In addition to being a target of the virus, the kidney also seems to have a substantial influence on the outcomes of the disease. METHODS: Data was obtained by a comprehensive and non-systematic search in the PubMed, Cochrane, Scopus and SciELO databases, using mainly the terms "SARS-CoV-2", "COVID-19", "chronic kidney disease", "renal transplantation", acute kidney injury" and "renal dysfunction" Discussion: The membrane-bound angiotensin-converting enzyme 2 is the receptor for SARS-CoV- -2, and this interaction may lead to an imbalance of the Renin-Angiotensin System (RAS), associated with worse clinical presentations of COVID-19, including acute pulmonary injury, hyperinflammatory state and hematological alterations. In the framework of renal diseases, the development of acute kidney injury is associated mostly with immune alterations and direct cytopathic lesions by the virus, leading to higher mortality. As for chronic kidney disease, the patients at a non-terminal stage have a worse prognosis, while the hemodialysis patients appear to have mild courses of COVID-19, probably due to lower chances of being affected by the cytokine storm. Furthermore, the current scenario is unfavorable to kidney donation and transplantation. The relationship between COVID-19 and immunosuppression in kidney transplantation recipients has been greatly discussed to determine whether it increases mortality and how it interacts with immunosuppressive medications. CONCLUSION: The kidney and the RAS exert fundamental roles in the SARS-CoV-2 infection, and more research is required to have a complete understanding of the repercussions caused by COVID-19 in renal diseases.