Topically Applied Taurine Chloramine Protects against UVB-Induced Oxidative Stress and Inflammation in Mouse Skin

Excessive exposure to solar light, especially its UV component, is a principal cause of photoaging, dermatitis, and photocarcinogenesis. In searching for candidate substances that can effectively protect the skin from photodamage, the present study was conducted with taurine chloramine (TauCl), formed from taurine in phagocytes recruited to inflamed tissue. Irradiation with ultraviolet B (UVB) of 180 mJ/cm2 intensity caused oxidative damage and apoptotic cell death in the murine epidermis. These events were blunted by topically applied TauCl, as evidenced by the lower level of 4-hydroxynonenal-modified protein, reduced proportions of TUNEL-positive epidermal cells, and suppression of caspase-3 cleavage. In addition, the expression of two prototypic inflammatory enzymes, cyclooxygenase-2 and inducible nitric oxide synthase, and transcription of some pro-inflammatory cytokines (Tnf, Il6, Il1b, Il10) were significantly lower in TauCl-treated mice than vehicle-treated control mice. The anti-inflammatory effect of TauCl was associated with inhibition of STAT3 activation and induction of antioxidant enzymes, such as heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1, through activation of nuclear factor erythroid 2-related factor 2.

Rejuveinix Mitigates Sepsis-Associated Oxidative Stress in the Brain: Clinical Impact Potential in COVID-19 and Nervous System Disorders

Here, we demonstrate that our anti-sepsis drug candidate Rejuveinix (RJX), at a dose level that is >10-times lower than its maximum tolerated dose (MTD) for human subjects, improves the survival outcome in the LPS-GalN model of sepsis and multi-organ failure. One hundred (100) percent (%) of untreated control mice remained alive throughout the experiment. By comparison, 100% of LPS-GalN injected mice died at a median of 4.6 hours. In contrast to the invariably fatal treatment outcome of vehicle-treated control mice, 40% of mice treated with RJX (n=25) remained alive with a 2.4-fold longer median time survival time of 10.9 hours (Log-rank X2=20.60, P<0.0001). Notably, RJX increased the tissue levels of antioxidant enzymes SOD, CAT, and GSH-Px, and it reduced oxidative stress in the brain. These findings demonstrate the clinical impact potential of RJX as a neuroprotective COVID-19 and sepsis drug candidate, which is currently being evaluated in a placebo-controlled, double-blind Phase II multi-institutional US study in hospitalized patients with COVID-19 associated viral sepsis.

Oxidized phosphatidylcholines trigger ferroptosis in cardiomyocytes during ischemia/reperfusion injury

Myocardial ischemia/reperfusion (I/R) injury increases the generation of oxidized phosphatidylcholines (OxPCs) which results in cell death. However, the mechanism by which OxPCs mediate cell death is largely unknown. The aim of this study was to determine the mechanisms by which OxPC triggers cardiomyocyte cell death during reperfusion injury. Cardiomyocyte viability, bioenergetic response and calcium transients were determined in the presence of OxPCs. Fragmented OxPCs resulted in a decrease in cell viability with POVPC and PONPC having the most potent cardiotoxic effect in both a concentration and time dependent manner (P<0.05). POVPC and PONPC also caused a significant decrease in Ca2+ transients and net contraction in isolated cardiomyocytes compared to vehicle treated control cells (P<0.05). PONPC depressed maximal respiration rate (p<0.01; 54%) and spare respiratory capacity (p<0.01; 54.5%). Notably, neither caspase 3 activation or TUNEL staining was observed in cells treated with either POVPC or PONPC. Further, cardiac myocytes treated with OxPCs were indistinguishable from vehicle treated control cells with respect to nuclear HMGB1 activity. Glutathione peroxidase 4 activity was markedly suppressed in cardiomyocytes treated with POVPC and PONPC. Importantly, cell death induced by OxPCs could be suppressed E06 Ab, directed against OxPCs or by ferrostatin. The findings of the present study suggest that OxPCs disrupt mitochondrial bioenergetics, calcium transients and provoke wide spread cell death through ferroptosis during I/R. Neutralization of OxPC with E06 or with ferrostatin-1 prevents cell death during reperfusion. Our study demonstrates a novel signaling pathway that operationally links generation of OxPC during cardiac I/R to ferroptosis.

Rejuveinix Mitigates Sepsis-Associated Oxidative Stress in the Brain of Mice: Clinical Impact Potential in COVID-19 and Nervous System Disorders

Here, we demonstrate that our anti-sepsis and COVID-19 drug candidate Rejuveinix (RJX) substantially improves the survival outcome in the LPS-GalN animal model of sepsis and multi-organ failure. One hundred (100) percent (%) of untreated control mice remained alive throughout the experiment. By comparison, 100% of LPS-GalN injected mice died at a median of 4.6 hours. In contrast to the invariably fatal treatment outcome of vehicle-treated control mice, 40% of mice treated with RJX (n=25) remained alive with a 2.4-fold longer median time survival time of 10.9 hours (Log-rank X2=20.60, P<0.0001). Notably, RJX increased the tissue levels of antioxidant enzymes SOD, CAT, and GSH-Px, and reduced oxidative stress in the brain. These findings demonstrate the clinical impact potential of RJX as a neuroprotective COVID-19 and sepsis drug candidate.

Evaluation of YashtimadhuKalpa formulation as Neuro-nutrient for Learning and Memory improvement in experimental animals

The unique functions of the brain are learning, memory, and ability to find objects, recollecting them, and cognition. The foremost intention of the study is to appraise the memory-enhancing potential of “YashtimadhuKalpa” using Wistar rats. The formulation YashtimadhuKalpawas prepared using various ingredients and was evaluated for memory-enhancing activity by using Morris water test and elevated plus maze apparatus for the parameter like transfer latency. The formulation - YashtimadhuKalpa (75, 150, and 300 mg/kg, p.o.) used for consecutive four weeks significantly reduced TL at the 29th day as correlated to the respective control sets, show enhancement in memory. All doses of formulation notably decreased EL of rats when checked for Day 1, day 15 and on day 30th as related to the control and showed noteworthy enhancement of learning and memory. Among all the doses, the higher dose at 300 mg/kg, p.o. Presents a highly important effect on TL as related to the vehicle-treated control set. The decline of transfer latency dose-dependently proved its potency against Neurodegeneration and confirmed its nootropic activity.

Increased Endocannabinoid Signaling Reduces Social Motivation in Intact Rats and Does Not Affect Animals Submitted to Early-Life Seizures

The early life status epilepticus (SE) causes high anxiety and chronic socialization abnormalities, revealed by a low preference for social novelty and deficit in social discrimination. This study investigated the involvement of the endocannabinoid system on the sociability in this model, due to its role in social motivation regulation. Male Wistar rats at postnatal day 9 were subjected to pilocarpine-induced neonatal SE and controls received saline. From P60 the groups received vehicle or JZL195 2 h before each behavioral test to increase endocannabinoids availability. In the sociability test, animals subjected to neonatal SE exhibited impaired sociability, characterized by social discrimination deficit, which was unaffected by the JZL195 treatment. In contrast, JZL195-treated control rats showed low sociability and impaired social discrimination. The negative impact of JZL195 over the sociability in control rats and the lack of effect in animals subjected to neonatal SE was confirmed in the social memory paradigm. In this paradigm, as expected for vehicle-treated control rats, the investigation toward the same social stimulus decreased with the sequential exposition and increased toward a novel stimulus. In animals subjected to neonatal SE, regardless of the treatment, as well as in JZL195-treated control rats, the investigation toward the same social stimulus was significantly reduced with no improvement toward a novel stimulus. Concerning the locomotion, the JZL195 increased it only in control rats. After behavioral tests, brain tissues of untreated animals were used for CB1 receptor quantification by Elisa and for gene expression by RT-PCR: no difference between control and experimental animals was noticed. The results reinforce the evidence that the early SE causes chronic socialization abnormalities, revealed by the low social interest for novelty and impaired social discrimination. The dual FAAH/MAGL inhibitor (JZL195) administration before the social encounter impaired the social interaction in intact rats with no effect in animals subjected to early-life seizures.

Inhibition of UCHL1 by LDN-57444 attenuates Ang II–Induced atrial fibrillation in mice

Atrial fibrillation (AF) is the most common human arrhythmia in clinical practice and may be promoted by atrial inflammation and fibrosis. Ubiquitination is an important posttranslational modification process that is reversed by deubiquitinating enzymes (DUBs). DUBs play critical roles in modulating the degradation, activity, trafficking, and recycling of substrates. However, less research has focused on the role of DUBs in AF. Here, we investigated the effect of ubiquitin C-terminal hydrolase 1 (UCHL1), an important DUB, on the development of AF induced by angiotensin II (Ang II). Male wild-type mice were treated with the UCHL1 inhibitor LDN57444 (LDN) at a dose of 40 μg/kg and infused with Ang II (2000 ng/kg/min) for 3 weeks. Our results showed that Ang II-infused wild-type (WT) mice had higher systolic blood pressure and an increased incidence and duration of AF. Conversely, this effect was attenuated in LDN-treated mice. Moreover, the administration of LDN significantly reduced Ang II-induced left atrial dilation, fibrosis, inflammatory cell infiltration, and reactive oxygen species (ROS) production. Mechanistically, LDN treatment inhibited the activation of multiple signaling pathways (the AKT, ERK1/2, HIF-1α, and TGF-β/smad2/3 pathways) and the expression of CX43 protein in atrial tissues compared with that in vehicle-treated control mice. Overall, our study identified UCHL1 as a novel regulator that contributes to Ang II-induced AF and suggests that the administration of LDN may represent a potential therapeutic approach for treating hypertensive AF.

Ceftazidime-Avibactam in Combination With Fosfomycin: A Novel Therapeutic Strategy Against Multidrug-Resistant Pseudomonas aeruginosa

Previously, by targeting penicillin-binding protein 3, Pseudomonas-derived cephalosporinase (PDC), and MurA with ceftazidime-avibactam-fosfomycin, antimicrobial susceptibility was restored among multidrug-resistant (MDR) Pseudomonas aeruginosa. Herein, ceftazidime-avibactam-fosfomycin combination therapy against MDR P. aeruginosa clinical isolate CL232 was further evaluated. Checkerboard susceptibility analysis revealed synergy between ceftazidime-avibactam and fosfomycin. Accordingly, the resistance elements present and expressed in P. aeruginosa were analyzed using whole-genome sequencing and transcriptome profiling. Mutations in genes that are known to contribute to β-lactam resistance were identified. Moreover, expression of blaPDC, the mexAB-oprM efflux pump, and murA were upregulated. When fosfomycin was administered alone, the frequency of mutations conferring resistance was high; however, coadministration of fosfomycin with ceftazidime-avibactam yielded a lower frequency of resistance mutations. In a murine infection model using a high bacterial burden, ceftazidime-avibactam-fosfomycin significantly reduced the P. aeruginosa colony-forming units (CFUs), by approximately 2 and 5 logs, compared with stasis and in the vehicle-treated control, respectively. Administration of ceftazidime-avibactam and fosfomycin separately significantly increased CFUs, by approximately 3 logs and 1 log, respectively, compared with the number at stasis, and only reduced CFUs by approximately 1 log and 2 logs, respectively, compared with the number in the vehicle-treated control. Thus, the combination of ceftazidime-avibactam-fosfomycin was superior to either drug alone. By employing a "mechanism-based approach" to combination chemotherapy, we show that ceftazidime-avibactam-fosfomycin has the potential to offer infected patients with high bacterial burdens a therapeutic hope against infection with MDR P. aeruginosa that lack metallo-β-lactamases.

GENERATION OF REACTIVE OXYGEN SPECIES IN RAT EPIDIDYMAL SPERMATOZOA AFTER CYCLOPHOSPHAMIDE TREATMENT

Objective: The aim of this study was to examine the effect of an anticancer drug cyclophosphamide (CPA) on generation of reactive oxygen species (ROS) in epididymal spermatozoa of Wistar rat, Rattus norvegicus. Methods: For this purpose, the rats were injected intraperitoneally with different doses of CPA (5 mg, 15 mg, and 20 mg/Kg BW for 2 weeks).Results: Treatment resulted into significantly increased level of ROS in CPA-treated groups when compared to the vehicle-treated control group.Conclusion: The results revealed that CPA has deleterious effect on the sperm morphology and physiology, which is dose and duration dependent and at certain doses cause the production of a number of reactive molecules and free radicals derived from molecular oxygen consequently resulting into adverse effect on the sperm function and hence on reproduction.

Protective Effect of Tempol on Buthionine Sulfoximine-Induced Mitochondrial Impairment in Hippocampal Derived HT22 Cells

Using a simulated oxidative stress model of hippocampus-derived immortalized cell line (HT22), we report that prooxidant buthionine sulfoximine (BSO, 1 mM, 14 h), without adversely affecting cell viability or morphology, induced oxidative stress by inhibiting glutathione synthesis. BSO treatment also significantly reduced superoxide dismutase (SOD) activity (p<0.05) and significantly lowered total antioxidant capacity (p<0.001) in HT22 cells when compared to vehicle treated control cells. Antioxidant tempol, a piperidine nitroxide considered a SOD mimetic, reversed BSO-induced decline in SOD activity (p<0.01) and also increased BSO-induced decline in total antioxidant capacity (p<0.05). Interestingly, BSO treatment significantly reduced mitochondrial oxygen consumption (p<0.05), decreased mitochondrial membrane potential (p<0.05), and lowered ATP production (p<0.05) when compared to vehicle treated control cells, collectively indicative of mitochondrial impairment. Antioxidant tempol treatment mitigated all three indicators of mitochondrial impairment. We postulate that BSO-induced oxidative stress in HT22 cells caused mitochondrial impairment, and tempol by increasing SOD activity and improving antioxidant capacity presumably protected the cells from BSO-induced mitochondrial impairment. In conclusion, present study provides an interesting simulation of oxidative stress in hippocampal cells, which will serve as an excellent model to study mitochondrial functions.