Brain-derived extracellular vesicles mediate traumatic brain injury associated multi-organ damage

Traumatic brain injury (TBI) can negatively impact systemic organs, which can lead to more death and disability. However, the mechanism underlying the effect of TBI on systemic organs remains unclear. In previous work, we found that brain-derived extracellular vesicles (BDEVs) released from the injured brain can induce systemic coagulation with a widespread fibrin deposition in the microvasculature of the lungs, kidney, and heart in a mouse model of TBI. In this study, we investigated whether BDEVs can induce heart, lung, liver, and kidney injury in TBI mice. The results of pathological staining and related biomarkers indicated that BDEVs can induce histological damage and systematic dysfunction. In vivo imaging system demonstrated that BDEVs can gather in systemic organs. We also found that BDEVs could induce cell apoptosis in the lung, liver, heart, and kidney. Furthermore, we discovered that BDEVs could cause multi-organ endothelial cell damage. Finally, this secondary multi-organ damage could be relieved by removing circulating BDEVs. Our research provides a novel perspective and potential mechanism of TBI-associated multi-organ damage.

Simulation of COVID-19 symptoms in a genetically engineered mouse model: implications for the long haulers

The ongoing pandemic (also known as coronavirus disease-19; COVID-19) by a constantly emerging viral agent commonly referred as the severe acute respiratory syndrome corona virus 2 or SARS-CoV-2 has revealed unique pathological findings from infected human beings, and the postmortem observations. The list of disease symptoms, and postmortem observations is too long to mention; however, SARS-CoV-2 has brought with it a whole new clinical syndrome in "long haulers" including dyspnea, chest pain, tachycardia, brain fog, exercise intolerance, and extreme fatigue. We opine that further improvement in delivering effective treatment, and preventive strategies would be benefited from validated animal disease models. In this context, we designed a study, and show that a genetically engineered mouse expressing the human angiotensin converting enzyme 2; ACE-2 (the receptor used by SARS-CoV-2 agent to enter host cells) represents an excellent investigative resource in simulating important clinical features of the COVID-19. The ACE-2 mouse model (which is susceptible to SARS-CoV-2) when administered with a recombinant SARS-CoV-2 spike protein (SP) intranasally exhibited a profound cytokine storm capable of altering the physiological parameters including significant changes in cardiac function along with multi-organ damage that was further confirmed via histological findings. More importantly, visceral organs from SP treated mice revealed thrombotic blood clots as seen during postmortem examination. Thus, the ACE-2 engineered mouse appears to be a suitable model for studying intimate viral pathogenesis thus paving the way for identification, and characterization of appropriate prophylactics as well as therapeutics for COVID-19 management.

Defense of COVID-19 by Human Organoids

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has created an immense menace to public health worldwide, exerting huge effects on global economic and political conditions. Understanding the biology and pathogenesis mechanisms of this novel virus, in large parts, relies on optimal physiological models that allow replication and propagation of SARS-CoV-2. Human organoids, derived from stem cells, are three-dimensional cell cultures that recapitulate the cellular organization, transcriptional and epigenetic signatures of their counterpart organs. Recent studies have indicated their great values as experimental virology platforms, making human organoid an ideal tool for investigating host-pathogen interactions. Here, we summarize research developments for SARS-CoV-2 infection of various human organoids involved in multiple systems, including lung, liver, brain, intestine, kidney and blood vessel organoids. These studies help us reveal the pathogenesis mechanism of COVID-19, and facilitate the development of effective vaccines and drugs as well as other therapeutic regimes.

Untangling COVID-19 and autoimmunity: Identification of plausible targets suggests multi organ involvement

Underlying mechanisms of multi-organ manifestations and exacerbated inflammation in COVID-19 are yet to be delineated. The hypothesis of SARS-CoV-2 triggering autoimmunity is gaining attention and, in the present study, we have identified 28 human proteins harbouring regions homologous to SARS-CoV-2 peptides that could possibly be acting as autoantigens in COVID-19 patients displaying autoimmune conditions. Interestingly, these conserved regions are amongst the experimentally validated B cell epitopes of SARS-CoV-2 proteins. The reported human proteins have demonstrated presence of autoantibodies against them in typical autoimmune conditions which may explain the frequent occurrence of autoimmune conditions following SARS-CoV-2 infection. Moreover, the proposed autoantigens' widespread tissue distribution is suggestive of their involvement in multi-organ manifestations via molecular mimicry. We opine that our report may aid in directing subsequent necessary antigen-specific studies, results of which would be of long-term relevance in management of extrapulmonary symptoms of COVID-19.

The dynamic association between COVID-19 and chronic disorders: An updated insight into prevalence, mechanisms and therapeutic modalities

The devastating pandemic of coronavirus disease 2019 (COVID-19) has caused thousands of deaths and left millions of restless patients suffering from its complications. Increasing data indicate that the disease presents in a severe form in patients with pre-existing chronic conditions like cardiovascular diseases, diabetes, respiratory system diseases, and renal diseases. This denotes that these patients are more susceptible to COVID-19 and have higher mortality rates compared to patients with no comorbid conditions. Several factors can explain the heightened susceptibility and fatal presentation of COVID-19 in these patients, for example, the enhanced expression of the angiotensin-converting enzyme-2 (ACE2) in specific organs, cytokine storm, and drug interactions contribute to the increased morbidity and mortality. Adding to the findings that individuals with pre-existing conditions may be more susceptible to COVID-19, it has also been shown that COVID-19 can induce chronic diseases in previously healthy patients. Therefore, understanding the interlinked relationship between COVID-19 and chronic diseases helps in optimizing the management of susceptible patients. This review comprehensively described the molecular mechanisms that contribute to worse COVID-19 prognosis in patients with pre-existing comorbidities such as diabetes, cardiovascular diseases, respiratory diseases, gastrointestinal and renal diseases, blood disorders, autoimmune diseases, and finally, obesity. It also focused on how COVID-19 could, in some cases, lead to chronic conditions as a result of long-term multi-organ damage. Lastly, this work carefully discussed the tailored management plans for each specific patient population, aiming to achieve the best therapeutic outcome with minimum complications.

Nephroprotective effect of Costus afer on lead induced kidney damage in albino rats

BACKGROUND

Lead is a nephrotoxicant probably implicated in the rising incidence of chronic kidney injury in sub-Sahara Africa. With the prohibitive cost and unavailability of metal chelators, chronic kidney disease CKD prevention is very difficult hence the search for affordable alternative. Costus afer have been shown to be organo-protective. The present research investigated the nephroprotective effect of aqueous leaf extract of Costus afer on lead induced nephrotoxicity in male rats.

METHODS

Adult male rats were weight matched into five groups of five rats each. Groups 1 & 2 serve as normal and toxic control receiving deionized and leaded (CH₃COO)₂Pb. 3H₂O water respectively. Groups 3, 4 and 5 were administered peroral 750, 1500 and 2250 mg/kg of aqueous leaf extract of Costus afer respectively while receiving Pb²⁺ water ad libitum. Hematological, antioxidant and histological parameters obtained from the result serve as scientific evidence in the study.

RESULTS

Costus afer treatment significantly reversed (P < 0.05) the decrease in the levels of gluthatione peroxidase (GSH-PX), superoxide dismutase (SOD), catalase (CAT), Glutathione-S-trasferase activity (GST) seen in the lead acetate only treated group. Similarly, the increased malondialdehyde (MDA) level in the lead acetate only treated group was significantly (P < 0.05) reduced in the Costus afer treated groups. There were significant (P < 0.05) decreases in serum serum level of sodium (146 ± 2.1 to 133 ± 6.0) and potassium (5.1 ± 0.4 to 4.4 ± 0.3) in lead acetate alone and treated group respectively. Also recorded was a significant (P < 0.05) decrease in serum levels of total protein and albumin (67 ± 7.9 to 47 ± 5.0 g/dl) and (45 ± 4.4 to 33 ± 5.5 g/dl) in lead acetate alone and Costus afer treated groups respectively.

CONCLUSIONS

Aqueous leaf extract of Costus afer may be nephroprotective in albino rats.