Intranuclear Delivery of HIF-1α-TMD Alleviates EAE via Functional Conversion of TH17 Cells

T helper 17 (TH17) cells are involved in several autoimmune diseases such as multiple sclerosis (MS) and rheumatoid arthritis (RA). In addition to retinoic acid receptor-related orphan nuclear receptor gamma t (ROR-γt), hypoxia-inducible factor-1α (HIF-1α) is essential for the differentiation and inflammatory function of TH17 cells. To investigate the roles of HIF-1α in the functional regulation of TH17 cells under the normal physiological condition without genetic modification, the nucleus-transducible form of transcription modulation domain (TMD) of HIF-1α (ntHIF-1α-TMD) was generated by conjugating HIF-1α-TMD to Hph-1 protein transduction domain (PTD). ntHIF-1α-TMD was effectively delivered into the nucleus of T cells without cellular cytotoxicity. ntHIF-1α-TMD significantly blocked the differentiation of naïve T cells into TH17 cells in a dose-dependent manner via IL-17A and ROR-γt expression inhibition. However, T-cell activation events such as induction of CD69, CD25, and IL-2 and the differentiation potential of naïve T cells into TH1, TH2, or Treg cells were not affected by ntHIF-1α-TMD. Interestingly, TH17 cells differentiated from naïve T cells in the presence of ntHIF-1α-TMD showed a substantial level of suppressive activity toward the activated T cells, and the increase of Foxp3 and IL-10 expression was detected in these TH17 cells. When mRNA expression pattern was compared between TH17 cells and ntHIF-1α-TMD-treated TH17 cells, the expression of the genes involved in the differentiation and functions of TH17 cells was downregulated, and that of the genes necessary for immune-suppressive functions of Treg cells was upregulated. When the mice with experimental autoimmune encephalomyelitis (EAE) were treated with ntHIF-1α-TMD with anti-IL-17A mAb as a positive control, the therapeutic efficacy of ntHIF-1α-TMD in vivo was comparable with that of anti-IL-17A mAb, and ntHIF-1α-TMD-mediated therapeutic effect was contributed by the functional conversion of TH17 cells into immune-suppressive T cells. The results in this study demonstrate that ntHIF-1α-TMD can be a new therapeutic reagent for the treatment of various autoimmune diseases in which TH17 cells are dominant and pathogenic T cells.

Age-Associated Increase in Thrombogenicity and Its Correlation with von Willebrand Factor

Endothelial cells that cover the lumen of all blood vessels have the inherent capacity to express both pro and anticoagulant molecules. However, under normal physiological condition, they generally function to maintain a non-thrombogenic surface for unobstructed blood flow. In response to injury, certain stimuli, or as a result of dysfunction, endothelial cells release a highly adhesive procoagulant protein, von Willebrand factor (VWF), which plays a central role in formation of platelet aggregates and thrombus generation. Since VWF expression is highly restricted to endothelial cells, regulation of its levels is among the most important functions of endothelial cells for maintaining hemostasis. However, with aging, there is a significant increase in VWF levels, which is concomitant with a significant rise in thrombotic events. It is not yet clear why and how aging results in increased VWF levels. In this review, we have aimed to discuss the age-related increase in VWF, its potential mechanisms, and associated coagulopathies as probable consequences.

Effect of Dietary Fermentable Carbohydrate Supplementation on Amino Acid Homeostasis

Objectives Homeostasis of amino acids (AA) such as branched chain AAs (BCAAs), and aromatic AAs are associated with glucose regulation. Fermentable carbohydrates (FC), such as xylooligosaccharide (XOS), have been shown to improve glucose and lipid metabolism. Therefore, we aim to study the potential of dietary FC to modulate systemic and tissue specific amino acid (AA) homeostasis in normal physiological condition. Two FCs of different molecular size were included in this study, XOS (0.3–1 kDa) and a new sulfated fucose containing polysaccharide (SPS) isolated from seaweed (82 kDa). Methods Male C57BL6 mice at age 7 week were randomized into three groups and fed AIN93M, AIN93M supplemented with 2% XOS or SPS (w/w) for 8 weeks (n = 6–8/group). SPS was prepared from Laminaria japonica. At the end of the intervention, fasting serum samples were collected and processed for glucose, insulin, AA analysis. Liver and skeletal muscle samples were frozen and processed for AA analysis. Results Blood glucose was significantly lower in XOS-fed mice but not SPS-fed mice compared to mice fed the control AIN93M diet. No significant differences in blood insulin, lipids, AA as well as body weight and fat depots were observed among the three experimental groups (XOS, SPS and control). In skeletal muscle, the concentration of total free AA, as well as 9 AAs (Asp, Glu, Arg, Tyr, Met, Phe and BCAAs) was significantly lower and 1 AA (Thr) was higher in SPS mice compared to control mice, while free AA levels in skeletal muscle were not significantly different between XOS and control mice. In liver, levels of total free AA, Arg, Thr and leucine metabolite ketoleucine were significantly lower in XOS mice compared to control mice. No significant change in free AA levels in liver was observed between SPS and control mice. Conclusions Our data show the differential modulation of systemic and tissue-specific AA and glucose homeostasis by dietary XOS and SPS intake, indicating the key role that AA signaling may play in metabolic homeostasis. Funding Sources This project was supported by the National Institutes of Health and UCLA Center for Human Nutrition.

The Effects of the Aqueous Extract of the Leaves of the Local Plant Eruca sativa on Lipid Profile and Some Minerals in the Blood of Male White Mice

Eruca sativa, commonly known as rocket salad, is a popular vegetable to which a wide range of health benefits are attributed. This study aimed to examine the effects of the aqueous extract of E. sativa leaves on lipid profile and some minerals, such as calcium and magnesium, in blood of male albino mice under normal physiological condition. Two experiments were separately conducted, each with eighteen male albino mice divided into 3 equal groups, which included control, treated group (1), and treated group (2) which were orally administrated with 0, 0.2 and 0.4 mg/kg body weight, respectively, of the leaves extract for 28 days. In the first experiment, serum lipid profile, including cholesterol, triglyceride, HDL, LDL and VLDL, were estimated. In the second experiment, serum calcium and magnesium were estimated. The results showed that E. sativa have effects on lipid profile by decreasing cholesterol, triglyceride, and LDL levels, but increasing that of HDL. In addition, E. sativa increased the levels of both calcium and magnesium. This study concludes that E. sativa leaves exerts possibly beneficial effect on lipid profile and calcium and magnesium levels in albino male mice under normal conditions.

Aldosterone: Implications in Diabetic Nephropathy

Objective: The focus of this review is to summarize the recent advancement to understand the molecular pathogenesis of diabetic nephropathy (DN). Also, to highlight the role of abnormal aldosterone secretion on the development and progression of diabetic nephropathy. Background: Diabetic Nephropathy (DN) is a progressive disease of nephron due to slow progressive failure of kidney tubule to perform its filtration process. It is often associated with proteinuria and glomerular stiffening which eventually leads to low glomerular filtration rate, finally succumbs the patient toward the end stage of kidney disease. The abnormal level of aldosterone in diabetes mellitus is a fatal combination to combat because of progressive development of diabetic nephropathy. Methods: We reviewed the literatures for implications of aldosterone in diabetic nephropathy. The literatures that were related to different aspects of diabetic nephropathy in relation to aldosterone were analyzed and summarized in this review article. Result & Conclusion: Aldosterone, a mineralocorticoid of corticosteroid hormones releases under the influence of adrenocorticotrophic hormone (ACTH) from zona glomerulosa of adrenal gland of kidney. In normal physiological condition it regulates the renin-angiotensin system of kidney, which regulates the resorption and conservation of sodium (Na+), potassium (K+) ions and water (H2O) from distal tubule. Aldosterone secretion, despite an important regulator to maintain the equilibrium of water and ions in the body, its non-regulated higher secretion gives rise to various pathological conditions. Additionally, we also discuss the risk factors associated with the use of mineralocorticoid receptor antagonist and renin-angiotensin-aldosterone therapy, and suggesting the need of robust and controlled methods to administer these drugs. Keywords: Aldosterone, Diabetic nephropathy (DN), Diabetes mellitus, Mmineralocorticoid receptor antagonists, Renin angiotensin system

The Role of Tenascin-C in Tissue Injury and Repair After Stroke

Stroke is still one of the most common causes for mortality and morbidity worldwide. Following acute stroke onset, biochemical and cellular changes induce further brain injury such as neuroinflammation, cell death, and blood-brain barrier disruption. Matricellular proteins are non-structural proteins induced by many stimuli and tissue damage including stroke induction, while its levels are generally low in a normal physiological condition in adult tissues. Currently, a matricellular protein tenascin-C (TNC) is considered to be an important inducer to promote neuroinflammatory cascades and the resultant pathology in stroke. TNC is upregulated in cerebral arteries and brain tissues including astrocytes, neurons, and brain capillary endothelial cells following subarachnoid hemorrhage (SAH). TNC may be involved in blood-brain barrier disruption, neuronal apoptosis, and cerebral vasospasm via the activation of mitogen-activated protein kinases and nuclear factor-kappa B following SAH. In addition, post-SAH TNC levels in cerebrospinal fluid predicted the development of delayed cerebral ischemia and angiographic vasospasm in clinical settings. On the other hand, TNC is reported to promote fibrosis and exert repair effects for an experimental aneurysm via macrophages-induced migration and proliferation of smooth muscle cells. The authors review TNC-induced inflammatory signal cascades and the relationships with other matricellular proteins in stroke-related pathology.

The function of multidrug resistance-associated protein 3 in the transport of bile acids under normal physiological and lithocholic acid-induced cholestasis conditions

Background: The role of multidrug resistance-associated protein 3 (Mrp3) in the transport of bile acid (BA) in drug-induced cholestasis have not been well studied. Objective: In this study, wild type and Mrp3 knockout (Mrp3-/- ) mice under normal physiological and lithocholic acid (LCA)-induced cholestatic conditions were employed to investigate the role of Mrp3 in BA transport. Method: The levels of BA in serum, liver, gallbladder, intestine, kidney, feces and urine were quantified in both wild type and Mrp3-/- mice via ultra-high performance liquid chromatography triple quadrupole mass spectrometry (UHPLC-MS/MS). Quantitative real time PCR (RT-PCR) analysis was used to measure the expression of genes related to the transport and synthesis of BA. Results: The results showed that the liver did not suffer more serious damage as a result of cholestasis when Mrp3 was depleted. The level of some individual bile acids changed apparently in the compartments of enterohepatic circulation (EHC) between the two control and model groups, respectively, but the level of serum total bile acid was only slightly reduced for Mrp3-/- groups. In addition, the level of BA-related efflux transporters and synthases increased significantly when Mrp3 was knocked out under normal physiological condition, but negligible alteration of them appeared under cholestatic condition. Conclusion: Our results indicated that Mrp3 could be responsible for the transport of some specific bile acids, and part of the Mrp3 role could be compensated for by other transporters. Moreover, Mrp3 deficiency has a direct effect on the expression of BA-related synthases and efflux transporters under normal physiological condition, but this effect could be less prominent under cholestatic condition. This study could provide much valuable insight into the physiological function of Mrp3 in the transport of bile acids.

Are Hsp90 inhibitors good candidates against Covid-19?

: Drug reposition, or repurposing, has become a promising strategy in therapeutics due to its advantages in several aspects of drug therapy. General drug development is expensive and can take more than 10 years to go through the designing, development, and necessary approval steps. However, established drugs have already overcome these steps and thus a potential candidate may be already available decreasing the risks and costs involved. Viruses invade cells, usually provoking biochemical changes, leading to tissue damage, alteration of normal physiological condition in organisms and can even result in death. Inside the cell, the virus finds the machinery necessary for its multiplication, as for instance the protein quality control system, which involves chaperones and Hsps (heat shock proteins) that, in addition to physiological functions, help in the stabilization of viral proteins. Recently, many inhibitors of Hsp90 have been developed as therapeutic strategies against diseases such as the Hsp90 inhibitors used in anticancer therapy. Several shreds of evidence indicate that these inhibitors can also be used as therapeutic strategies against viruses. Therefore, since a drug treatment for COVID-19 is urgently needed, this review aims to discuss the potential use of Hsp90 inhibitors in the treatment of this globally threatening disease.

Analysis of two mechanisms of telomere maintenance based on the theory of g-Networks and stochastic automata networks

* Background Telomeres, which are composed of repetitive nucleotide sequences at the end of chromosomes, behave as a division clock that measures replicative senescence. Under the normal physiological condition, telomeres shorten with each cell division, and cells use the telomere lengths to sense the number of divisions. Replicative senescence has been shown to occur at approximately 50–70 cell divisions, which is termed the Hayflick’s limit. However, in cancer cells telomere lengths are stabilized, thereby allowing continual cell replication by two known mechanisms: activation of telomerase and Alternative Lengthening of Telomeres (ALT). The connections between the two mechanisms are complicated and still poorly understood. * Results In this research, we propose that two different approaches, G-Networks and Stochastic Automata Networks, which are stochastic models motivated by queueing theory, are useful to identify a set of genes that play an important role in the state of interest and to infer their previously unknown correlation by obtaining both stationary and joint transient distributions of the given system. Our analysis using G-Network detects five statistically significant genes (CEBPA, FOXM1, E2F1, c-MYC, hTERT) with either mechanism, contrasted to normal cells. A new algorithm is introduced to show how the correlation between two genes of interest varies in the transient state according not only to each mechanism but also to each cell condition. * Conclusions This study expands our existing knowledge of genes associated with mechanisms of telomere maintenance and provides a platform to understand similarities and differences between telomerase and ALT in terms of the correlation between two genes in the system. This is particularly important because telomere dynamics plays a major role in many physiological and disease processes, including hematopoiesis.

NOX4 Deficiency Exacerbates the Impairment of Cystatin C-Dependent Hippocampal Neurogenesis by a Chronic High Fat Diet

Hippocampal neurogenesis is linked with a cognitive process under a normal physiological condition including learning, memory, pattern separation, and cognitive flexibility. Hippocampal neurogenesis is altered by multiple factors such as the systemic metabolic changes. NADPH oxidase 4 (NOX4) has been implicated in the regulation of brain function. While the role of NOX4 plays in the brain, the mechanism by which NOX4 regulates hippocampal neurogenesis under metabolic stress is unclear. In this case, we show that NOX4 deficiency exacerbates the impairment of hippocampal neurogenesis by inhibiting neuronal maturation by a chronic high fat diet (HFD). NOX4 deficiency resulted in less hippocampal neurogenesis by decreasing doublecortin (DCX)-positive neuroblasts, a neuronal differentiation marker, and their branched-dendrites. Notably, NOX4 deficiency exacerbates the impairment of hippocampal neurogenesis by chronic HFD. Moreover, NOX4 deficiency had a significant reduction of Cystatin C levels, which is critical for hippocampal neurogenesis, under chronic HFD as well as normal chow (NC) diet. Furthermore, the reduction of Cystatin C levels was correlated with the impairment of hippocampal neurogenesis in NOX4 deficient and wild-type (WT) mice under chronic HFD. Our results suggest that NOX4 regulates the impairment of Cystatin C-dependent hippocampal neurogenesis under chronic HFD.